ThinkPad 355

The ThinkPad 355 is an entry-level notebook featuring the classic ThinkPad design in a lightweight chassis.

The following tables show a brief overview of the system features.

Models 355x, 360x

Feature

Description

Processor Bus Architecture Memory (Standard) Memory (Option) CMOS RAM VGA Video Diskette Drive (Removable) Hard Disk Drive (Removable) Audio Card Internal Modem Card PCMCIA

• 355x, 360, 360C, 360Cs, 360P SL Enhanced 486SX 33 MHz, solder mounted on the system board • 360CE, 360CSE, 360PE SL Enhanced 486DX2 50/25 MHz on the system board • AT Bus • VESA Local Bus for video subsystem 4MB (on the system board) 2, 4, 8, 16MB, Basic IC DRAM card (max. 16 MB) 128 Bytes • 355, 360 -  9.5-inch (diagonally), 64 gray level STN LCD monochrome • 355Cs, 360Cs, 360CSE, 360P, 360PE -  9.5-inch (diagonally), 256/4096 color, DSTN LCD color • 355C, 360C, 360CE -  8.4-inch (diagonally), 256/256K color, TFT LCD color 0.720, 1.2, 1.44MB (3-mode), 3.5-inch • 355x -  125MB, 2.5-Inch -  250MB, 2.5-Inch • 360x -  170MB, 2.5-Inch -  340MB, 2.5-Inch • Standard (360PE) • Option (other Model 360x) • Standard (355x) • Option (360x) • 360x -  One Type-III or Two Type-II • 355x -  One Type-III or Type-II

Model 370C

Feature

Description

Processor Bus Architecture Memory (Standard) Memory (Option) CMOS RAM VGA Video Diskette Drive (Removable) Hard Disk Drive (Removable) Audio Card PCMCIA

Intel® DX4 75MHz on the system board • AT Bus • VESA Local Bus for video subsystem 4MB (on the system board) • 2, 4, 8, 16MB, Basic IC DRAM card (max. 16 MB) • 4, 8, 16MB, DIMM card (max. 32MB) • DIMM card adapter 128 Bytes • 10.4-inch (diagonally), 256/256K colors TFT LCD color • 0.720, 1.2, 1.44MB (3-mode), 3.5-inch • 340MB, 2.5-inch • 540MB, 2.5-inch • 810MB, 2.5-Inch Standard in Japan and European countries. One Type-III or two Type-II

Model 750x

Feature

Description

Processor Bus Architecture Memory (Standard) Memory (Maximum) CMOS RAM VGA Video Diskette Drive (Removable) Hard Disk Drive (Removable) Audio Card PCMCIA

• 750x -  486SL 33MHz, solder mounted on the system board • 750Ce - SL Enhanced 486DX2 50MHz on the processor card • AT Bus • VESA Local Bus for video subsystem (750Ce) 4MB (on the system board) 2, 4, 8, 16MB, IC DRAM card (max. 20 MB) • 750x -  256 Bytes • 750Ce -  256 Bytes • 750 -  9.5-inch (diagonally), 64 gray level STN LCD monochrome • 750C, 755Ce -  10,4-inch (diagonally), 256 color, TFT LCD color • 750Cs -  9.5-inch (diagonally), 256 color, STN LCD color • 750P -  9.5-inch (diagonally), 64 gray level STN LCD monochrome 0.720, 1.2, 1.44, 2.88MB (4-mode) 3.5-inch • 170MB, 2.5-inch • 340MB, 2.5-inch Standard One Type-III or Two Type-II

Models 755C, 755Cs

Feature

Description

Processor Bus Architecture Memory (Standard) Memory (Option) CMOS RAM VGA Video Diskette Drive (Removable) Hard Disk Drive (Removable) Audio Card PCMCIA

• SL Enhanced 486DX2 50MHz on the system board • 486DX4 75MHz on the processor card • AT Bus • VESA Local Bus for video subsystem 4MB (on the system board) • 2, 4, 8, 16MB, IC DRAM card (max. 16 MB) • 4, 16MB, DIMM card (max. 32 MB) • DIMM card adapter 128 Bytes • 755C -  10.4-inch (diagonally), 256/256K color, TFT LCD color • 755Cs -  9.5-inch (diagonally), 256/4096 color, DSTN LCD color • 0.720, 1.2, 1.44MB (3-mode), 3.5-inch • 0.720, 1.2, 1.44, 2.88MB (4-mode), 3.5-inch • 170MB, 2.5-inch • 340MB, 2.5-Inch • 540MB, 2.5-Inch Microphone and headphone jacks with built in microphone One Type-III or two Type-II

The ThinkPad 355 is an entry-level notebook featuring the classic ThinkPad design in a lightweight chassis.

This section provides information about the following:

• Memory Checkout
• System Board and Processor Checkout (370C, 750Ce, 755C, 755Cs)
• Keyboard / Auxiliary Input Device Checkout
• TrackPoint II Checkout
• Pen and Digitizer Checkout (360P, 360PE, 750P)
• Audio Card Checkout
• Diskette Drive Test
• Power Systems Checkout
• Power Management Features

Use the following procedure as a guide for computer problems.

NOTE: The diagnostic tests are intended to test only IBM products. Non-IBM products, prototype cards, or modified options can give false errors and invalid system responses.

1. Obtain the failing symptoms in as much detail as possible.- Verify the symptoms by attempting to recreate the failure by  running the diagnostic test or by repeating the same operation.

   NOTE: To run the diagnostics, refer to 'How to Run the Diagnostics'

   • Use the following table with the verified symptom to determine  which page to go to. Search the symptoms column  and find the description  that best matches your symptom, then go to the page shown in the Go to column.

Symptom	Go to
Power failure. (The power indicator does not go on or stay on.)	'Power Systems Checkout'
POST does not complete. No beeps/error code are indicated.	'Symptom-to-FRU Index', and then use the 'No Beep Symptoms' table.
POST beeps, but no error codes are displayed.	'Symptom-to-FRU Index', and then use the 'Beep Symptoms' table.
POST detected an error and displayed numeric error codes.	'Symptom-to-FRU Index', and then use the 'Numeric Error Codes' table.
The diagnostic test detected an error and displayed an FRU code.	'FRU Codes'
The configuration is not the same as the installed devices.	'Checking the Installed Devices List'
Other symptoms (such as LCD display problems).	'Symptom-to-FRU Index', and then use 'Other Miscellaneous symptoms' tables.
Symptoms cannot be recreated. (Intermittent problems.)	Use the customer reported symptoms and go to 'Symptom-to-FRU Index'
TV Tuner Problems	See 'TV Tuner'

Use either the TrackPoint II or the cursor move keys to interact with the tests. The Enter key works the same as selecting the OK icon to reply OK.

1. Press and hold the F1 key, then power-on the computer.  Hold the F1 key down until Easy-setup screen appears.- Select Test and press Enter.- Select a device and press Enter to run the test.- The test progress screen appears.- OK appears when the test ends without any errors.- Start the Advanced Diagnostic test by pressing Ctrl+A on the basic diagnostic menu screen.- Select Tool to install the tools.- Select a device, press the space key, and  install the tool. Multiple devices can be selected by repeating  this step.

             A **OK** mark appears for the selected device.
            - Select **OK** and press Enter
               if the selection is OK.- Select a device and press Enter to start the tests.- Select **Test All** to test all devices.- Select **Loop Test** to loop tests.
   
                     A loop option menu appears in which a device loop or all loop can be
                     selected. Select a device and press the **space** key to select
                     a device. Repeat this step to select multiple devices.
                     Press Enter to start the diagnostic loop. If no device is selected,
                     all device tests are looped.- To exit the loop,
                       keep pressing **Ctrl+Pause** until the test exits.
                       A beep sounds (750Ce, 755C, 755Cs) to notify
                       that the exit interrupt is sensed
                       by the test program.
   

Do the following to run the keyboard test.

1. Go to the advanced diagnostic screen menu by pressing Ctrl+A in Easy-Setup menu.
2. Go to the keyboard diagnostic test menu by pressing Ctrl+K .
3. Check that when each key is pressed, the key position on the  keyboard layout on the screen changes to be a black square.

NOTE: When a Fn key is pressed, the black square briefly appears.

This section provides information about the following:

  Numeric Error Codes <<-- Error Codes

The Symptom-to-FRU Index lists the symptoms and errors and the possible causes. The most likely cause is listed first.

NOTE: Perform the FRU replacement or actions in the sequence shown in the “FRU/Action“ columns. If a FRU did not solve the problem, put the original part back in the computer.

This index can also be used to help you decide which FRUs to have available when servicing a computer.

'Numeric error codes' show the errors detected in POST or system operation. In the following error codes, X can be any number.

If no codes are available, use narrative symptoms.

If the symptom is not listed, go to 'Undetermined Problems'

NOTE:

• For IBM devices not supported by the diagnostic codes  in this manual,  see the manual for that device.
• If the LCD is replaced with a new one,  see 'Digitizer Adjustment' to adjust the pen-point pressure.

Symptom/Error	FRU/Action
10X	1. System Board
110	1. Go to 'Memory Checkout' 2. IC DRAM Card or DIMM Card 3. System Board
111	1. Go to 'Memory Checkout' 2. Expansion Unit/Port Replicator 3. System Board
118 (Memory parity error was logged in CMOS.) (Go to 'Memory Checkout')	1. Run memory diagnostics to clear the error log.
158 (HDP was not set even though the supervisor password is set.)	1. Set a HDP.
159 (HDP is not set the same as the supervisor password.)	1. Set a correct HDP.
161	1. Go to 'Checking the Backup Battery' 2. Backup Battery 3. System Board
163 (Time and Date was not set.)	1. Set Time and Date. 2. System Board
173 (Configuration data were lost.)	1. Select OK in the error screen, then set time and date 2. Backup Battery 3. System Board
174 (Perform 'Checking the Installed Devices List' before changing any FRUs.)	1. Check Device Configuration. 2. System Board 3. Diskette Drive Assembly 4. Hard Disk Drive Assembly
175, 177, 178	1. System Board
183 (Incorrect password entered at the supervisor password prompt.)	1. Have the user examine the password.
184 (POP checksum error.)	1. Reset the POP in Easy-Setup.
185 (The startup sequence is not valid. Suspect that power was off when the startup sequence was being updated.)	1. Reset the startup sequence in Easy-Setup.
186	1. System Board
188	1. Set the system identification using the ThinkPad 750Ce hardware maintenance diskette. NOTE: You can use this maintenance diskette for all Models.
190 (Depleted battery pack was installed when the power was on.)	1. Go to 'Checking the Battery Pack'
191XX	1. System Board 2. Processor card (370C, 750Ce, 755C, and 755Cs)
195 (The configuration read from the hibernation area does not match the actual configuration.)	1. Check if the configuration was changed. For example, check if the disk drive from another computer.
196 (Read error occurred in the hibernation area of the HDD.)	1. Run the hard disk drive test. 2. Hard Disk Drive
197 (The computer memory size is not equal to the hibernation area size on the HDD.)	1. Have the user disable then enable hibernation mode.
199XX	1. System Board
1XX	1. System Board
2XX	1. Go to 'Memory Checkout' 2. IC DRAM Card, DIMM, or DIMM Adapter 3. System Board
301, 303, 304, 305, 3XX	1. Go to 'Keyboard/Aux. Inp.-Device Checkout' 2. Keyboard 3. Interposer Card 4. External Numeric Keypad 5. External Keyboard 6. Keyboard/Mouse Cable 7. System Board
601, 6XX	1. Go to 'Diskette Drive Test' 2. Diskette Drive Assembly 3. Diskette 4. System Board
602 (Diskette read error.)	1. Go to 'Diskette Drive Test' 2. Diskette 3. Diskette Drive Assembly
604 (Non-acceptable ID was read from the diskette drive.)	1. Go to 'Diskette Drive Test' 2. Diskette Drive Assembly 3. System Board
11XX	1. Serial Device (First) 2. Communication Cable 3. System Board
12XX	1. Serial Device (Second) 2. Communication Cable 3. System Board
17XX	1. Hard Disk Drive 2. System Board
24XX	1. System Board
4101	1. Reseat the LCD connector Pen see '2070 LCD Assembly' 2. LCD Assembly 3. System Board
808X	1. PCMCIA Slot Assembly 2. PCMCIA Device 3. System Board
860X (Pointing device error when TrackPoint II is disabled.)	1. External Mouse 2. External Keyboard 3. System Board
861X (Pointing device error when TrackPoint II is enabled.)	1. Reseat the keyboard Track Point II cable at the interposer card 355x, 360x See '1040 Keyboard Unit' 370C, 750x, 755C, 755Cs See '2040 Keyboard Unit' 2. Keyboard 3. External Mouse 4. System Board
I9990301	1. Reseat the boot device.
I9990302	2. Check the startup sequence for the
I9990305	correct boot device. 3. Check that operating system has no failure, or is installed correctly.
I9990303	1. System Board
Other codes not listed above	1. Go to 'Undetermined Problems'

If an error is detected by the diagnostic tests, a four-digit FRU code is displayed. The FRU code indicates two suspected FRUs. Replace the FRU that is indicated by the two leftmost digits first, then replace the FRU indicated by the two rightmost digits No FRU is assigned to code 00. If only one FRU is suspected, the other FRU code is filled with zeros. See the referenced page before replacing the FRU.

FRU Code	FRU / Action
10	System Board
11	Processor Card (370C, 750Ce, 755C, and 755Cs)
15	Audio Card
20	Memory (See 'Memory Checkout')
30	Reserved
32	External Keyboard
33	External Mouse
40	LCD Assembly (See 'Digitizer Adjustment' and important (note for 'LCD Related Symptoms')
45	External CRT
50	Reseat the Drive (FDD-1) Diskette Drive (FDD-1)
51	Reseat the Drive (FDD-2) Diskette Drive (FDD-2)
60	Reseat the Hard Disk Drive (HDD-1) Hard Disk Drive (HDD-1)
61	Reseat the Hard Disk Drive (HDD-2) Hard Disk Drive (HDD-2)
70	PCMCIA-2 (Replicator)
80	Cellular Modem (370C, 750Ce, 755C, and 755Cs)
81	Internal Modem Card
90	Reserved

NOTE: The device ID and error codes are used to indicate the detail portion of the FRU which caused the error. If replacing a FRU does not correct a problem, see the Device ID or error code from the previous failure. If they have changed, the cause might be because the new FRU is defective or that the FRU was incorrectly installed.

If the problem remains after replacement of the FRUs, go to 'Undetermined Problems'

Symptom/Error	FRU/Action
No beep, power-on indicator not on and a blank LCD during POST.	1. Go to 'Power Systems Checkout' 2. System Board 3. DC/DC Card 4. Power sources
No beep, power-on indicator on, and a blank LCD during POST.	1. System Board 2. DC/DC Card 3. Processor Card (370C, 750Ce, 755C, 755Cs)
No beep, power-on indicator on, and a blinking cursor only during POST.	1. System Board 2. Processor Card (370C, 750Ce, 755C, and 755Cs) 3. DC/DC Card
No beep during POST but system runs correctly	1. Turn the volume up and check the speaker 2. Speaker 3. Audio Card 4. DC/DC Card

Symptom/Error	FRU/Action
Continuous beeps.	System Board
One beep and a blank unreadable, or flashing LCD.	1. Reseat all LCD connectors 2. LCD Assembly 3. System Board 4. DC/DC Card
One beep, and the message 'Unable to access boot source'	1. Boot device 2. System Board
One long, two short beeps and a blank or unreadable LCD.	1. System Board 2. LCD Assembly
One long beep followed by four short beeps each time the power switch is operated. (System cannot power-on due to low battery voltage.)	Connect the AC Adapter or install a fully-charged battery.
One beep every second. (System is shutting down due to low battery voltage.)	Connect the AC Adapter or install a fully-charged battery (allows system to complete shutdown before changing the battery)
Two short beeps with error codes.	POST error. See 'Numeric Error Codes'
Two short beeps with blank screen.	System Board

Intermittent system hang problems can be caused by a variety of reasons that have nothing to do with a hardware defect such as: cosmic radiation, electrostatic discharge, or software errors. FRUs replacement should only be considered when a recurring problems exits.

When analyzing the intermittent problem, do the following:

1. Run the advanced diagnostic test for the system board in loop mode  at least 10 times.
2. If no error is detected, do not replace any FRUs.
3. If any error is detected, replace the FRU shown by the FRU code.  Rerun the test to verify that no more errors exist.

  FRU Removals and Replacements

Removals - Models 355x, 360x

Removals - Models 370C, 750x, 755C, 755Cs

This section contains information about removals and replacements.

• The system board is sensitive to, and can

be damaged by,   electrostatic discharge. Establish personal grounding
 by touching a ground point with one hand before touching these units.

  An electrostatic discharge(ESD) strap must be used to establish
 personal grounding.

• Do not damage any part. Only certified trained personnel  should service the computer.
• The arrows in the “Removals and Replacements“ section show  the direction of movement to remove a FRU, or to turn a screw to release  the FRU. The arrows are marked in numeric order, in square callouts, to  show the correct sequence of removal.
• When other FRUs must be removed before removing the failing FRU,  they are listed at the top of the page.
• To replace a FRU, reverse the removal procedure and follow any  notes that pertain to replacement. See 'Locations' for internal  cable connections and arrangement information.
• When replacing a FRU, use the correct screw size as shown in the  procedures.

Before removing any FRU, power-off the computer, unplug all power cords from electrical outlets, remove the battery pack, and then disconnect any interconnecting cables.

The battery pack contains small amounts of nickel. Do not disassemble it, throw it into fire or water, or short-circuit it. Dispose of the battery pack as required by local ordinances or regulations.

Before the computer is powered-on after FRU replacement, make sure all screws, springs, or other small parts, are in place and are not left loose inside the computer. Verify this by shaking the computer and listening for rattling sounds. Metallic parts or metal flakes can cause electrical shorts.

  Removals Models 355x, 360x

  Removals Models 370C, 750x, 755C, 755Cs

System - Front View (750, 750Cx, 755Cx, 370C, 360x, 355x)

System - Front View (750P, 360P, 360PE)

System Rear View - All Models

System Board (Top View)

System Board (Bottom View)

Processor Card (370C, 750Ce, 755C, 755Cs)

DC / DC Card - Top View

Interposer Card - All Models (Front View)

System - Front View (750, 750Cx, 755Cx, 370C, 360x, 355x)

1. LCD- Contrast Control

   NOTE: The Model 360 does not have a contrast control.

   The Model 755C has one of two types of LCD:

   one with a contrast control and one without.

   • Brightness Control- Status Indicator

     See 'Status Indicators'

     • External Input Device Connector
     • PCMCIA Slot
     • PCMCIA Release Lever
     • Keyboard
     • LCD and Keyboard Latch
     • TrackPoint II
     • Click Button
     • Diskette-Eject Button
     • Diskette Drive
     • Fn Key

System Front View - (750P, 360P, 360PE)

1. Convertible LCD
2. Contrast Control
3. Brightness Control
4. Status Indicator
5. External Input Device Connector
6. PCMCIA Slot
7. PCMCIA Release Lever
8. Keyboard
9. LCD and Keyboard Latch
10. Hard Disk Drive Compartment
11. Battery Compartment
12. Click Buttons
13. Diskette-Eject Button
14. Diskette Drive
15. Fn Key
16. TrackPoint II
17. Stylus Pen

Common Parts Listing

This section contains FRUs common to most IBM portable, laptop, and notebook computers.

External Diskette Drives

5.25-Inch Diskette Drives:
360KB External (4869-001)	72X6759
360KB External (4869-501)	72X6768
1.2MB External (4869-002)	15X7993
1.2MB External (4869-502)	15X7994
Hard Disk Drive.
1.2GB HDD (for all 9545)	85G8549
5.25-Inch Drive Adapter	72X6757
5.25-Inch Drive Adapter/A	15F7996
5.25-Inch External Diskette Drive Cable
(from system board to adapter)	27F4211
Diskette Drive Bus Adapter	72X8524

CD-ROM Drives

Enhanced Internal CD-ROM II Drive
(Eject button below slot)	61G1901
Internal CD-ROM I Drive
(Eject button above slot)	81F7930
)81F7930Terminator Kit (for	59F3530
)81F7930Cleaning Kit (for
(Disks, CD Caddy)	59F3562
Internal CD-ROM II Drive
(Eject button below slot)	92F0084
)92F0084Terminator Kit (for	92F0082
)92F0084Media Kit (for
(No cleaning necessary,
Test Disk, CD Caddy)	31F4232
Signal Cable	34F0043
Power Cable	72X8521
Remote ID Switch Cable (3510)	92F0086
Audio Card, Cable, Screws (3510)	92F0085
CD Caddy	22F9419
Rail Kit (3510)	34F0041
Headphones	53F3610

SCSI Adapters, Terminators, Cables

SCSI Adapter/A (without Cache)	85F0002
SCSI Internal Cable	64F4127
SCSI Adapter/A (with Cache)	85F0063
)85F0063Terminator, External (for	33F8464
)85F0063Terminator, Internal (for	34F0025
)85F0002Terminator, Internal (for	57F2870
SCSI Fast Adapter (16 bit)	92F0330
)92F0330SCSI External Cable (for	32G4089
)92F0330SCSI Internal Cable (for	32G0084
Terminator, Inline (space permitting)	92F0412

Rewritable Optical Drives

3.5-Inch Rewritable Optical Drive	92F0167
Rewritable Optical Cartridge	38F8647
Rewritable Optical Cartridge (5 Pack)	38F8646
)92F0167Drive Mounting Slide (for	85F0022
)92F0167Tray with Bezel (for	85F0021
)92F0167Objective Lens Cleaner (for	38F8681
)92F0167Prism Lens Cleaner (for	38F8682
3.5-Inch Enhanced Rewritable Optical Drive	92F0167
Mounting Tray	92F0269
Mounting Tray/Bezel (Model 3510)	92F0268

External Keyboard/Mouse

Keyboard Cable	72X8537
Mouse	61X8923
Mouse Ball and Pop-Off Retainer	33F8461
Mouse Ball and Twist-Off Retainer	33F8462
)33G5420Mouse (New Style) (	06H4595
Mouse Retainer Ring	33G5417
Miniature Mouse	95F5723

Enhanced Keyboards (101/102 Key)

Country	FRU P/N
Arabic	1391490
Belgian	1391414
Canadian French	1392011
Cyrillic	1393866
Danish	1391407
Dutch	1391511
French	1391402
German	1391403
Greek	1393285
Hebrew	1391408
Italian	1393395
Latin American Spanish	1392015
Norwegian	1391409
Portuguese	1391410
Russian/Cyrillic	1395622
Spanish	1391405
Swedish/Finnish	1391411
Swiss	1391412
Swiss/French	1395881
Swiss/German	1395882
Turkish	1393286
U.K. English	1391406
U.S. English (E/ME/A use only)	1396790
U.S. English	1392090
Yugoslavian	1393669

Optional Enhanced Keyboards (101/102 Key)

with PS/2 Style Cable	59G7980
with AT Style Cable	59G7981
with 25mm PS/2 Trackball	59G7982
with 25mm Serial Trackball	59G9757

Keybutton Kits (101/102 Key)

Keybutton Kits (R), Belgian	1392033
Keybutton Kits (R), Canadian French	1392032
Keybutton Kits (R), Danish	1392026
Keybutton Kits (R), Dutch	1392034
Keybutton Kits (R), French	6447047
Keybutton Kits (R), German	6447048
Keybutton Kits (R), Italian	6447049
Keybutton Kits (R), Norwegian	1392028
Keybutton Kits (R), Portuguese	1392029
Keybutton Kits (R), Spanish	6447050
Keybutton Kits (R), Spanish / Latin	1392035
Keybutton Kits (R), Swedish	1392030
Keybutton Kits (R), Swiss / French / German	1392031
Keybutton Kits (R), U.K. English	6447046
Keybutton Kits, U.S. English	6447045

Japanese Keyboard Type 2 (106 Key, DBCS Support)

Japanese Keyboard	94X1110
Keyboard Cable	94X1147

Space-Saving Keyboards (84/85 Key)

Canadian French	1396046
Spanish/Latin	1396047
U.S. English	1393290
Cable Assembly, External	1393082

Tools and Miscellaneous

Audio Wrap Cable	66G5180
Ethernet BNC T-Connector	84F8207
Ethernet BNC 50-ohm Terminator
(2 required)	85F0037
Grounding Wire Set	38F4684
Keyboard Key Cap Removal Tool	6110464
PC Test Card	33G4703
Screwdriver Kit	95F3598
SCSI Terminator
(any SCSI device, space permitting)	92F0142
SCSI Terminator Kit
(R-PAC Terminator Modules (3) for 40, 60,
80, 120, and 160MB SCSI Hard Disk Drives)	92F0143
Wrap Plug Ethernet D-Shell	85F0036
Wrap Plug, Tri-Connector	72X8546
Wrap Plug (6157 Tape Attachment Adapter/A)	4178459
Wrap Plug (Token-Ring Network Adapter/A)	6165899
Plastic Envelope (For Wrap Plug)	6138013

ThinkPad Common Parts List

 Safety Notice 2

Some standby batteries contain a small amount of nickel and cadmium. Do not disassemble it, recharge it, throw it into fire or water, or short-circuit it. Dispose of the battery as required by local ordinances or regulations. Use only the battery in the appropriate parts listing. Use of an incorrect battery can result in ignition or explosion of the battery.

Certaines batteries de secours contiennent du nickel et du cadmium. Ne les démontez pas, ne les rechargez pas, ne les exposez ni au feu ni à l'eau. Ne les mettez pas en court-circuit. Pour les mettre au rebut, conformez-vous à la réglementation en vigueur. Lorsque vous remplacez la pile de sauvegarde ou celle de l'horloge temps réel, veillez à n'utiliser que les modèles cités dans la liste de pièces détachées adéquate. Une batterie ou une pile inappropriée risque de prendre feu ou d'exploser.

Die Bereitschaftsbatterie, die sich unter dem Diskettenlaufwerk befindet, kann geringe Mengen Nickel und Cadmium enthalten. Sie darf nur durch die Verkaufsstelle oder den IBM Kundendienst ausgetauscht werden. Sie darf nicht zerlegt, wiederaufgeladen, kurzgeschlossen, oder Feuer oder Wasser ausgesetzt werden. Die Batterie kann schwere Verbrennungen oder Verätzungen verursachen. Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll beachten. Beim Ersetzen der Bereitschafts- oder Systembatterie nur Batterien des Typs verwenden, der in der Ersatzteilliste aufgeführt ist. Der Einsatz falscher Batterien kann zu Entzündung oder Explosion führen.

Alcune batterie di riserva contengono una piccola quantità di nichel e cadmio. Non smontarle, ricaricarle, gettarle nel fuoco o nell'acqua né cortocircuitarle. Smaltirle secondo la normativa in vigore (DPR 915/82, successive disposizioni e disposizioni locali). Quando si sostituisce la batteria dell'RTC (real time clock) o la batteria di supporto, utilizzare soltanto i tipi inseriti nell'appropriato Catalogo parti. L'impiego di una batteria non adatta potrebbe determinare l'incendio o l'esplosione della batteria stessa.

Algunas baterías de reserva contienen una pequeña cantidad de níquel y cadmio. No las desmonte, ni recargue, ni las eche al fuego o al agua ni las cortocircuite. Deséchelas tal como dispone la normativa local. Utilice sólo baterías que se encuentren en la lista de piezas. La utilización de una batería no apropiada puede provocar la ignición o explosión de la misma.

 Safety Notice 4

The lithium battery can cause a fire, explosion, or severe burn. Do not recharge it, remove its polarized connector, disassemble it, heat it above 100°C (212°F), incinerate it, or expose its cell contents to water. Dispose of the battery as required by local ordinances or regulations. Use only the battery in the appropriate parts listing. Use of an incorrect battery can result in ignition or explosion of the battery.

La pile de sauvegarde contient du lithium. Elle présente des risques d'incendie, d'explosion ou de brûlures graves. Ne la rechargez pas, ne retirez pas son connecteur polarisé et ne la démontez pas. Ne l'exposez pas à une temperature supérieure à 100°C, ne la faites pas brûler et n'en exposez pas le contenu à l'eau. Mettez la pile au rebut conformément à la réglementation en vigueur. Une pile inappropriée risque de prendre feu ou d'exploser.

Die Systembatterie ist eine Lithiumbatterie. Sie kann sich entzünden, explodieren oder schwere Verbrennungen hervorrufen. Batterien dieses Typs dürfen nicht aufgeladen, zerlegt, über 100 C erhitzt oder verbrannt werden. Auch darf ihr Inhalt nicht mit Wasser in Verbindung gebracht oder der zur richtigen Polung angebrachte Verbindungsstecker entfernt werden. Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll beachten. Beim Ersetzen der Batterie nur Batterien des Typs verwenden, der in der Ersatzteilliste aufgeführt ist. Der Einsatz falscher Batterien kann zu Entzündung oder Explosion führen.

La batteria di supporto e una batteria al litio e puo incendiarsi, esplodere o procurare gravi ustioni. Evitare di ricaricarla, smontarne il connettore polarizzato, smontarla, riscaldarla ad una temperatura superiore ai 100 gradi centigradi, incendiarla o gettarla in acqua. Smaltirla secondo la normativa in vigore (DPR 915/82, successive disposizioni e disposizioni locali). L'impiego di una batteria non adatta potrebbe determinare l'incendio o l'esplosione della batteria stessa.

La bateria de repuesto es una bateria de litio y puede provocar incendios, explosiones o quemaduras graves. No la recargue, ni quite el conector polarizado, ni la desmonte, ni caliente por encima de los 100°C (212°F), ni la incinere ni exponga el contenido de sus celdas al agua. Deséchela tal como dispone la normativa local.

 Safety Notice 5

If the LCD breaks and the fluid from inside the LCD gets into your eyes or on your hands, immediately wash the affected areas with water for at least 15 minutes. Seek medical care if any symptoms from the fluid are present after washing.

Si le panneau d'affichage à cristaux liquides se brise et que vous recevez dans les yeux ou sur les mains une partie du fluide, rincez-les abondamment pendant au moins quinze minutes. Consultez un médecin si des symptômes persistent après le lavage.

Die Leuchtstoffröhre im LCD-Bildschirm enthält Quecksilber. Bei der Entsorgung die örtlichen Bestimmungen für Sondermüll beachten. Der LCD-Bildschirm besteht aus Glas und kann zerbrechen, wenn er unsachgemäß behandelt wird oder der Computer auf den Boden fällt. Wenn der Bildschirm beschädigt ist und die darin befindliche Flüssigkeit in Kontakt mit Haut und Augen gerät, sollten die betroffenen Stellen mindestens 15 Minuten mit Wasser abgespült und bei Beschwerden anschließend ein Arzt aufgesucht werden.

Nel caso che caso l'LCD si dovesse rompere ed il liquido in esso contenuto entrasse in contatto con gli occhi o le mani, lavare immediatamente le parti interessate con acqua corrente per almeno 15 minuti, poi consultare un medico se i sintomi dovessero permanere.

Si la LCD se rompe y el fluido de su interior entra en contacto con sus ojos o sus manos, lave inmediatamente las áreas afectadas con agua durante 15 minutos como mínimo. Obtenga atención medica si se presenta algún síntoma del fluido despues de lavarse.

Three power management modes are provided by the computer to save power consumption and prolong battery power.

Standby Mode When in standby mode the following occurs:

• The LCD backlight turns off.
• The hard disk motor stops.
• The CPU clock is set to the lowest speed.

Events that cause entering of standby mode:

• Standby requested by the Fn key. (Fn+F3)
• No activity under auto-standby enabled by the feature  utility.

Events that cause exiting or resuming of standby mode:

• (Resume) Any key operation.

Suspend Mode

When in suspend mode, the following, in addition to the four actions of standby mode, occur:

• The LCD power is powered-off.
• The hard disk is powered-off.
• The CPU is stopped.

In the ThinkPad Features Program, the computer can be set to 'Will not suspend even if LCD is closed'..

When the computer is powered with ac power and is used with one of the following IBM PC cards, the computer enters standby mode, the PC card and application program remain active.

• 3270 Emulation Credit Card Adapter
• 5250 Emulation Credit Card Adapter
• Token-Ring 16/4 Credit Card Adapter
• Credit Card Adapter for Ethernet

In the following condition, the computer cannot enter the suspend mode.

• While the communication link is running.
• When a serial mouse or other pointing device is selected  in the Config menu of Easy-Setup.

Events that cause entering of suspend mode:

• Suspend mode is requested by the Fn key (Fn+F4).
• The LCD is closed.
• The keyboard is opened.
• The specified time has elapsed from the last operation with  the keyboard, mouse, hard disk drive, parallel connector,  diskette drive, or the AC Adapter is plugged in.  The time is specified by Suspend Timer in the ThinkPad Features program.
• The battery condition is low. The battery power indicator  blinks (orange).
• The PS2 OFF command is set in  the ThinkPad Features program.

Events that cause exiting or resuming of suspend mode:

• (Resume) The LCD is opened.
• (Resume) The keyboard is closed.
• (Resume) Real time clock alarm signaled.
• (Resume) Ring indicator  (RI) signaled by serial or PCMCIA device.
• (Resume) The Fn key is pressed.
• (Exit) Timer conditions are satisfied  to enter hibernation mode.

Hibernation Mode

When in hibernation mode, the following occurs:

• The system status, RAM, VRAM, and setup  data are stored on the hard disk.
• The system is powered-off.

The computer cannot enter hibernation mode when:

• A serial mouse or other pointing device is selected in the Config menu.- The computer is powered with ac power and one of the following  IBM PC cards is used.

  • PCMCIA Data/FAX Modem
  • High Speed PCMCIA Data/FAX Modem
  • 3270 Emulation Credit Card Adapter
  • 5250 Emulation Credit Card Adapter
  • Token-Ring 16/4 Credit Card Adapter
  • Credit Card Adapter for Ethernet

Events that cause entering of hibernation mode:

• The hibernation mode is requested by the Fn  key (Fn+F12).
• Timer conditions are satisfied in suspend mode.
• Critical low battery condition.

Event that causes exiting of hibernation mode.

• The power-on switch is operated.

When power is turned on, the hibernation history of the boot record on the hard disk is recognized and system status is restored from the hard disk to resume operation.

Symptom/Error	FRU/Action
Power shut down during operation.	1. Go to 'Power Systems Checkout' 2. Battery Pack 3. Remove the battery pack and let it cool for two hours. 4. DC/DC Card 5. Power sources
The system will not power-off. (See 'Reset Pushbutton')	1. Press the Reset pushbutton. 2. System Board

1. Power-off the computer and unplug the AC Adapter  from the computer.
2. Open the keyboard, and remove the battery pack and the  diskette drive.
3. Remove the backup battery from the system board.
4. Measure the voltage of the backup battery.

Wire	Voltage (Vdc)
Red	+2.5 to +3.7
Black	Ground

• If the voltage is correct, replace the system board.
• If the voltage is not correct, the backup battery has been  discharged. Replace the backup battery.
• If the backup battery discharges quickly after replacement,  replace the system board.

Battery charging will not start until the Fuel-Gauge shows that less than 90% of the total power remains; with this condition the battery pack will charge to 100% of its capacity. This protects the battery pack from being over-charged or having a shortened life.

NOTE:

1. Models 355x and 360x battery pack does not  contain a microprocessor. In the following,  ignore any reference to the storage switch.- Before you perform the following procedure,  check the following:

   • The correct battery pack is used for the model.
   • The storage switch set to on (!).

   • Power-off the computer.- Remove the battery pack and measure the voltage between battery  terminals

     NOTE: The following figure hows the battery for the Model 370C,  750x, 755C, and 755Cs.  The battery for Models 355x and 360x, do not have the  storage switch, but the battery terminals are the same.

     

     Terminal	Voltage (V dc) / Signal
     1	+ 8.0 to + 16.0
     2	Send
     3	Thermal
     4	Ground (-)
     5	R1
     6	Select
     7	R2

     NOTE: Signal lines, not used in these steps,  are used for communication between the system and the battery.  The storage switch is used to control the power to the  internal microprocessor of the battery.  The storage switch should be  set to off (0) only when the battery is going to be kept in storage  for more than two months.

     • If the voltage is less than + 8.0 Vdc, the battery pack has  been discharged or is defective.  Recharge the battery.  If the recharging does not work,  go to Step 5 to check the charging circuit.

     If the voltage is still less than + 8.0 Vdc after the recharging,  replace the battery.- If the voltage is more than + 8.0 Vdc,  measure the resistance between  battery terminals 3 and 4.  The resistance must be 4 to 30 kilohms.

      If the resistance is not correct, replace the battery pack.
     
      If the resistance is correct, replace the DC/DC card.- To check the charging circuit, do the following.
         Plug in the AC Adapter with the battery pack removed, then
         power-on the computer.- Measure the charging voltage between DC/DC terminals
           1 (+) and 4 (-).- If the voltage is less then + 9.0 Vdc, replace the DC/DC card.
             If the voltage is more than + 9.0 Vdc, the charging circuit is
             working correctly, replace the battery pack.
     

NOTE:

1. Be careful that the computer does not fall backward when  the battery pack is removed.
2. Check that the keyboard latch springs are in place.

NOTE:

1. Be careful that the computer does not fall backward when  the battery pack is removed.
2. When replacing the battery pack,  check that the storage switch of the new battery  is set to the on (!) position.  Do not operate the storage switch of a battery that has been used  and is going to be re-used.
3. Check that the keyboard latch springs are in place.

You are here because the computer fails only when the AC Adapter is used.

• If the power problem occurs only when the port replicator is used,  replace the replicator.
• If the power-on indicator does not turn on, check the power  cord of the AC Adapter for correct continuity and installation.
• If the operational charge does not work, go to 'Checking Operational Charging'

NOTE: There are two types of adapters. The procedure for checking both types is the same.

1. Unplug the AC Adapter cable from the computer and  measure the output voltage at the plug of the AC Adapter cable.

Pin	Voltage (Vdc)
1	+19.0 to +21.0
2	Ground

• If the voltage is correct, replace the system board. If the  problem is not corrected, go to 'Undetermined Problems'
• If the voltage is not correct, go to the next step.
• Unplug the AC Adapter cable from the ac power outlet and wait  five minutes or longer to allow the over voltage protection circuit  to be fully discharged and initialized.
• Plug the AC Adapter cable into the ac power outlet.
• Measure the output voltage of the AC Adapter.
• If the voltage is still not correct, replace the AC Adapter.

NOTE: An audible noise from the AC Adapter does not always indicate a defective adapter.

To check operational charging, use a discharged battery pack or a battery pack that shows a yellow or orange battery status indicator when it installed in the computer.

Perform operational charging. If the battery status indicator turns orange and the battery charging indicator turns green within two minutes, replace the AC Adapter.

There are two types of adapters but the checkout procedure is the same for both of them.

1. Unplug the Car-Battery Adapter cable from the computer.- Plug the Car-Battery Adapter into the cigarette lighter socket.

   NOTE: If the adapter is already plugged in, reseat it.

   • Measure the output voltage of the Car-Battery Adapter cable.

   

   Pin	Voltage (Vdc)
   1	+19.0 to +21.0
   2	Ground

   • If the voltage is correct and the power-on indicator  on the Car-Battery Adapter is on all the time, the Car-Battery  is working correctly. Replace the system board.

     If the problem is not resolved when the system board is replaced,  go to 'Undetermined Problems'- If the voltage is outside the normal voltage range, do one of the  following:

     • Try the above test procedures in a different car,  if one is available.
     • Replace the Car-Battery Adapter if the computer works  correctly with the AC Adapter.

NOTE: If the output voltage from the cigarette lighter socket of the car is less than + 10.5 Vdc, the power-on indicator on the Car-Battery Adapter blinks and a continuous noise can be heard. The condition of the car battery should be checked by appropriate service personal.

The Car-Battery Adapterdoes not support operational charging.

There are two types of chargers, but checkout procedures are the same for both of them.

1. Ensure that the battery pack is  operating correctly. (See 'Checking the Battery Pack')- Connect the power cord to the quick charger and the other  end to an ac power outlet.  Ensure that the power-on indicator is on.

   • If the power-on indicator does not turn on, check the power cord  for correct continuity and installation.
   • If the problem is not corrected,  replace the quick charger or the power cord.

   • Install the battery pack into the quick charger.

   • If the charging indicator does not start blinking,  replace the quick charger.

1. Power-off the computer and unplug the AC Adapter  from the computer.- Open the keyboard, and remove the battery pack and the  diskette drive.- Remove the standby battery.- Measure the voltage of the standby battery.
   • - If the voltage between red and black
   • is 3.5 Vdc or greater, the voltage is
   • correct.
   • Go to Step 10
   • to verify standby battery operation.
   • If the voltage is less than 3.5 Vdc, go to the next step.
   • - Plug the AC Adapter
   • into the computer and power-on the computer.
   • Measure the output voltage at the connector on the system board.
   • 
   • - If the voltage is less than + 4.0 Vdc,
   • replace the DC/DC card. If the voltage is still low, replace the system
   • board.
   • If the voltage is more than + 4.0 Vdc, power-off the computer,
   • replace the standby battery, and go to the next step.
   • - Ensure that the AC Adapter is plugged into
   • the computer, then power-on the computer.
   • Charging of the standby battery starts.
   • A depleted battery needs approximately 30
   • minutes to be recharged to the operational voltage of + 3.5 Vdc.
   • Unplug the AC Adapter.
   • Verify the standby battery function by removing and installing
   • the battery pack during suspend mode.
   • **NOTE:**
   • Removing and installing the battery pack during suspend mode
   • should be done ****within one minute.****
   • The resume operation must start.
   • If the
   • resume operation does not work, switching of power from the battery
   • pack to standby battery
   • will not be correct. Replace the DC/DC card.
   • If replacing the DC/DC card does not resolve the problem, replace
   • the system board.

If power shut downs occur intermittently when using PCMCIA-2 devices via a port replicator, suspect an over-current problem. Some PCMCIA devices use more power, if the maximum usage of each device occurs simultaneously, the total current will exceed the limit, thereby causing a power shut down. Isolate this problem by removing one of the devices, and use the computer under the same condition to see whether a power shut down occurs. Do this procedure for all devices, then determine the cause. Use of the larger AC Adapter (50W, optional) is recommended, if one is not yet in use.

Use the ThinkPad Features program or PS2.EXE. to power-on the TV Tuner, then power-on the internal device in the diskette drive compartment.

  If power for the internal device is turned off when the TV Tuner is set up, nothing appears on the LCD display. Turn on power for the TV Tuner again.

• If you are using DOS, do one of the following:

• Power-on the computer and type PS2 from the  command prompt to start the ThinkPad Features program. Select Set Power Features from the ThinkPad Features  menu,then put a check mark at Internal Serial Port (or Diskette Drive Compartment )  under the Power for devices .  If you need help, press F1 to display the help menu.
• Type ps2 modem on from the command prompt,  press the Enter key to set the power ON.

• If you are using OS/2 or  Microsoft Windows, do the following:

  1. Power-on the computer and start the ThinkPad Features program.
  2. Select the Power icon, then move the pointer to Internal Serial Port (or Diskette Drive Compartment )  under the Power for devices and click the button to check mark it.
  3. Press the OK button.

If you suspect a problem with the Port Replicator, see 'Port Replicator Checkout' in the 'Common Devices Checkout' section for more information.

Use the following procedure to isolate a port replicator problem. A port replicator attaches to the system expansion connector at the rear of the computer.

1. Power-off the computer.- Remove the failing devices from the replicator.- Unplug the AC adapter from the replicator, if attached.- Remove the port replicator from the computer.- Reconnect the failing device directly to the computer.  (If another device occupies the connector, remove it first.)- Go to General Checkout and follow that procedure.- If the advanced diagnostic device test does not find an error,  suspect a problem with the port replicator  or the system expansion bus.- Power-off the computer and reconnect the port replicator.- Power-on the computer and run the following advanced diagnostic tests:

              - Serial port test with the wrap plug installed on the replicator.- Parallel port test with the wrap plug installed on the replicator.- PCMCIA-2 test with the PC test card installed.- FDD-2 (FDD-1 if no drive is installed in the computer)
                       drive test on the failing device.
   
              - If diagnostic errors appear, replace the replicator or diskette
                 drive attachment unit.
   
                 If the problem remains after the replacement, replace the
                 system board.
   
                - If power problems appear only when using the replicator, replace the
                   replicator.
   

If power shut downs occur intermittently when using PCMCIA-2 devices via a port replicator, suspect an over-current problem. Some PCMCIA devices use more power; if the maximum usage of each device occurs simultaneously, the total current will exceed the limit, thereby causing a power shut down. Isolate this problem by removing one of the devices, and use the computer under the same condition, and see whether a power shut down occurs. Do this procedure for all devices then determine the cause.

Customer purchase of the larger AC adapter (50W, optional) is recommended, if it is not yet in use.

Remove the external keyboard if the internal keyboard is to be tested.

If the internal keyboard does not work or an unexpected character appears, make sure that the three flexible cables extending from the keyboard are correctly seated in the connectors on the interposer card.

If the keyboard cable connection is correct, run the Keyboard Test by doing the following:

1. Go to diagnostic menu screen by pressing Ctrl+A in Easy-Setup screen.
2. Press Ctrl+K , the figure of the keyboard  appears on the screen.
3. Check that when each key is pressed, the key position  on the keyboard layout on the screen changes to be a black square.

NOTE: When a Fn key is pressed, the black square briefly appears.

If the tests detect a keyboard problem, do the following one at a time to correct the problem. Do not replace a non-defective FRU.

• Reseat the three cables.
• Replace the keyboard.
• Replace the interposer card.
• Replace the system board.

The following auxiliary input devices are supported for this computer.

• Numeric keypad
• Mouse (PS/2 compatible)
• External keyboard (with keyboard/mouse cable)

If any of the above devices do not work, reseat the cable connector and repeat the failing operation.

If the problem does not occur again, recheck the connector.

If the problem is not corrected, replace the device, and then the system board.

If the TrackPoint II will not work, check the configuration in Easy-Setup by selecting Keyboard from the Config menu.

If the configuration of the TrackPoint II disabled, select TrackPoint to enable it.

If this does not correct the TrackPoint II problem, continue with the following.

The TrackPoint II does automatic compensations to adjust the pointer sensor. During this process, the pointer moves on the screen automatically for a short time. This self-acting pointer movement can occur when a slight, steady pressure is applied to the TrackPoint II pointer while the computer is powered on or while the system is running, or re-adjustment is required because the temperature has exceeded its normal temperature range. This symptom does not indicate a hardware problem. No service actions are necessary* if the pointer movement stopsin a short period of time.

If a click button problem or pointing stick problem occurs, do the following:

1. Go to Easy-Setup screen.
2. Select an item with the pointing stick.
3. Press either the left or right click button.
4. Verify that both buttons work correctly.

If either the pointing stick or the click button will not work, do the following actions one at a time to correct the problem. Do not replace a non-defective FRU.

• Reseat the three keyboard cables.
• Replace the keyboard.
• Replace the interposer card.
• Replace the system board.

Do the following to run the audio tests.

NOTE: Refer to 'Product Overview' to see whether the audio card is standard or not.

1. Power-off the computer.- Insert the ThinkPad 750Ce hardware maintenance diskette  into diskette drive A and power-on the computer.

   NOTE: You can use this maintenance diskette for all Models.

   • Select the Audio Diagnostics from the main menu.- Select Tests from the menu bar and press Enter.- Select All tests from the pull-down menu and press Enter.

     Run options are set to test once and stop on error as defaults.  Other options can be selected by the pull-down menu of Setting-up.

     • Follow the instructions that  appear on the screen to proceed with the tests.
     • If the tests end and no errors are detected,  the “All tests passed OK message appears.
     • If an error is detected, the FRU code and error description message  appear.  Go to 'FRU Codes' and replace the FRU.
     • To exit from the test screen, press Esc .

Do the following to isolate the problem to a controller, drive, or diskette. A scratch, write enabled, non-defective 2HD diskette is required.

  **Make sure that the diskette does not have more than one label attached to it.

Multiple labels can cause damage to the drive or can cause the drive to fail.

1. Do the following to select the test device:

2. Select the advanced diagnostic mode and  select Tool,- Select the icon FDD-1 or FDD-2 and  press the space key.

   A **OK** mark appears next to the selected icon.
    Insert the **blank** diskette when instructed.
   

• Run the diskette drive test.- If the controller test detects an error, FRU code 10 appears.  Replace the system board.- If the controller test runs without errors,  the drive read/write tests start automatically.- If the drive test detects an error, FRU code 50 for FDD-1 or 51 for FDD-2 appears.  If the diskette itself is known to be good, replace the drive.- If the drive is attached through a Port Replicator  as FDD-1 or FDD-2 and the test detects errors,  move the drive to the computer's diskette drive connector directly,  and test it again as FDD-1.

        If no errors occur at the FDD-1 position, the drive is not defective.
        Go to ['Port Replicator Checkout'](#port-replicator-checkout) in 'Common Devices
        Checkout' section to isolate the replicator problem.
  
       - If the drive is attached through an Expansion Unit, go to the
          service manual of the Expansion Unit to isolate the problem.- If the drive is attached through a Diskette Drive Attachment Unit,
            replace the unit.
  

The TV Tuner Pack (hereafter called TV Tuner) is an option for watching TV programs or videos on the IBM TFT color notebook computer. The computer changes to TV reception when the removable diskette drive is replaced with the TV Tuner.

The TV screen and normal computer display are easily switched by using the Hot key on the front panel of the TV Tuner.

Identifying Names and Functions

The following figure and table show the names and functions of each part of the TV Tuner.

Icons          Functions
 Front Panel      Used to change the TV channels, switch TV mode
                  to computer mode, and operate most functions of
                  the TV Tuner.
 --------------------------------------------------------------
 Headphone Jack  

Connects the headphones.
Power Indicator  Shows the TV Tuner is powered on. -------------------------------------------------------------- Power Switch

Powered on and off the TV Tuner.
Hot Key

Switches between the TV screen and computer screen.
Up Switch

Increases the value such as the channel number.
Down Switch

Decreases the value such as the channel number.
Function Key

   Enters the mode to change the value of each function,
                  such as TV channel or color contrast.
 (See 'Using the Function Key')
 --------------------------------------------------------------
 TV/EXT Switch  

Switches the TV mode or external video mode.
Volume Knob

Controls the speaker volume.
Audio-In Jack

Connects the audio-in connector of the AV cable.
Video-In Jack

Connects video-in connector of the AV cable.
RF Connector

   Connects the active antenna unit or antenna cable.
 --------------------------------------------------------------

Using the Front Panel

The following table shows how to operate all functions of the TV Tuner with the controls on the front panel.

Key            Function
 Power

   Turns on the TV Tuner.
        This key is used only when the computer is turned on.
 Hot Key

   Switches computer display and TV screen.
Up

   Increases the value of parameters, Channel Number,
        Color, Tint, Brightness, Contrast, Auto Tuning Sensitivity,
        On-screen Message Selection.
 Down

   Decreases the value of parameters, Channel Number
        Color, Tint, Brightness, Contrast, Auto Tuning Sensitivity,
        On-screen Message Selection.
 Function

   Selects a function mode to adjust each function parameter.
        (See Using the Function Key)
 TV/Ext

   Switches the displayed video source between
        the receiving TV broadcast program and external devices such as
        VCR, video camera recorder, laser disk, and so on.

Symptom/Error	FRU/Action
Keyboard (one or more keys) does not work.	1. Reseat the three keyboard cables. 2. Keyboard 3. Interposer Card 4. System Board
TrackPoint II does not work.	1. Go to 'TrackPoint II Checkout' 2. Keyboard 3. Interposer Card 4. System Board
Pointer moves automatically or does not work correctly.	1. See 'TrackPoint II Checkout'

Symptom/Error	FRU/Action
The system will not suspend or resume by opening or closing the keyboard.	1. Go to 'Suspend Mode' and check that the computer can enter Suspend Mode 2. Go to Easy-Setup screen and press Fn+4. If the computer enters suspend mode suspect that the application program is defective. 3. DC/DC Card 4. Interposer Card 5. System Board
The system will not suspend or resume by opening or closing the LCD.	1. Go to 'Suspend Mode' and check that the computer can enter suspend mode. 2. Go to Easy-Setup screen and press Fn+4. If the computer enter suspend mode suspect that the application program is defective. 3. Interposer Card 4. DC/DC Card 5. System Board
Battery Fuel-Gauge does not go higher than 90%.	1. Go to 'Checking the Battery Pack' and see the note.
Audio problems.	1. Run the Audio Test. 2. Audio Card
Memory count (size) appears differently from actual size.	1. Go to 'Memory Checkout'
System configuration does not match the installed devices.	1. Go to 'Checking the Installed Devices List'
System hangs intermittently.	1. Go to 'Intermittent Problems'

The green LED on the PC test card turns on when the PCMCIA test is running. If the LED does not turn on, check that the card is installed correctly by reseating the card. If it still does not turn on after it is reseated, try using another slot for the test. If the LED still does not turn on and the test fails, replace the FRU shown in the diagnostic error code.

1 When removing the screw covers, use a small screwdriver as shown.

2  
When using a screwdriver to remove cover or latches, be careful not to:

• Scratch the surface of the computer.
• Break the latches.

3 Open the keyboard.

4 Remove the leaf-spring plate.

5 When unlatching the upper cover latches to remove the upper cover, use a small screwdriver as shown.

6 Remove the upper cover.

NOTE: To remove the upper cover, do not latch the keyboard. Lower the keyboard and remove the upper cover.

7 Disconnect the cables to remove the keyboard unit as shown.

  Do not pull the keyboard cables.

The keyboard cables can be damaged if the keyboard is disconnected without releasing the three latches 7

8 Remove the keyboard.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
2	Upper cover (2)	8 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

Notes for when replacing.

1. When replacing the keyboard,  check that the three cables are clean, and  inserted straight and fully into the connectors.  Slide both ends of each latch at the same time  to make sure that each cable is correctly inserted.

 
  While pressing the cables into place,  be careful not to break the flexible  cables.

Go to 'Keyboard / Auxiliary Input Device Checkout' and test all keys before returning the  computer to the customer.

• When replacing the upper cover,  insert the two latches located on the rear side of the cover  into the guide of the LCD foot, then push the right, left,  and front sides to snap them into place. Be careful not to damage the suspend/resume switch when  putting on the cover.

1 When removing the screw covers, use a small screwdriver as shown.

2  
When using a screwdriver to remove cover or latches, be careful not to:

• Scratch the surface of the computer.
• Break the latches.

3 Open the keyboard.

4 Remove the leaf-spring plate.

5 When unlatching the upper cover latches to remove the upper cover, use a small screwdriver as shown.

6 Remove the upper cover.

NOTE: To remove the upper cover, do not latch the keyboard. Lower the keyboard and remove the upper cover.

7 Disconnect the cables to remove the keyboard unit as shown.

 
Do not pull the keyboard cables.

The keyboard cables can be damaged if the keyboard is disconnected without releasing the three latches.

8 Remove the keyboard.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
2	Upper cover (2)	8 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

Notes for when replacing

1. When replacing the keyboard, check that  the three cables are clean, and  inserted straight and fully into the connectors.  Slide both ends of each latch at the same time  to make sure that each cable is correctly inserted.  Go to 'Keyboard / Auxiliary Input Device Checkout' and test all keys before returning the  computer to the customer.
2. When replacing the upper cover,  insert the two latches located rear side of the cover  into the guide of the foot of the LCD, push the right, left,  and front sides to snap into place. Be careful not to damage the suspend/resume switch  when putting on the cover.

1. Check that the backup  and standby batteries are seated correctly to prevent  damage to the diskette drive .
2. Do not put any pressure on the diskette drive cover. Remove the diskette drive exactly as shown in the figure.
3. Make sure that a diskette is not installed in the drive. Removing the drive with a diskette installed causes  bending or damaging the eject button.

After replacing the diskette drive, latch the removal strap into the correct position.

 

1. Check that the backup  battery and standby battery are seated correctly to prevent  damage to the diskette drive when replacing the diskette drive.
2. Do not put any pressure on the diskette drive cover. Remove the diskette drive exactly as shown in the figure.
3. Make sure that a diskette is not installed in the drive. Removing the drive with a diskette installed causes  bending or damaging the eject button.

After replacing the diskette drive, latch the removal strap into the correct position.

Use the following procedure to isolate the diskette problem to a controller, drive or diskette. A scratch, write-enabled 2HD diskette is required.

1. Select the icon FDD on the TEST MENU . By  doing this, the controller test and the drive  read/write test run.  If the controller test detects an error, FRU code 10 appears.  In this case, replace the system board.
2. If the controller test run without errors,  follow the instructions on the screen and insert a scratch  diskette.
3. If the drive test detects an error, FRU code 50 appears.  If the diskette media are known to be good, replace the drive or the  drive cable.

If the display problem occurs only when using an external display, use the following instructions to correct the problem.

Note: Before you replace a display, check the following list to see if it is connected correctly.

• 8506 and 8508 displays must be connected to an Image Adapter/A or an  Image-I Adapter/A.
• 63XX and 85XX systems support either 63XX or 85XX displays.
• 85XX systems with an XGA-2 adapter support 95XX displays.
• 95XX systems support either 63XX, 85XX, or 95XX displays.
• ThinkPad models support either 85XX or 95XX displays.

If the screen is rolling, replace the display assembly. If that does not correct the problem, replace FRUs in the following order until the problem goes away:

1. Video card
2. Display adapter (any type)
3. System board
4. Bus adapter (if used)

If the screen is not rolling, run the display self-test as follows:

1. Power-off the computer and display.
2. Disconnect the display signal cable.
3. Power-on the display.
4. Set the contrast to its maximum position.
5. Set the brightness control to the center detent position.

Check for the following conditions:

• You should be able to vary the screen intensity by adjusting the contrast  and brightness controls.
• The screen should be white or light gray,  with a black margin (test margin) on the screen. NOTE: The location of the test margin varies with the type of display. The  test margin might be on the top, bottom, or one or both sides.

If you do not see a test margin on the screen, replace the display. If there is a test margin on the screen, replace the system board.

On ThinkPad Models 700, 700C, 720C, 720C, do the following:

1. Video card
2. System board

The following auxiliary input devices may be available for IBM ThinkPad models.

• Numeric keypad
• Mouse (PS/2 compatible)
• External keyboard (with Keyboard/Miniature Mouse cable)

• If you suspect a problem with any of the auxiliary input devices  (listed above), replace the device.

If the problem is not corrected, replace the following FRUs one  at a time to correct the problem.

• Keyboard control card
• System board

• If the computer receives an incorrect keyboard response,  remove other external devices, check the keyboard connections, and recheck  the keyboard responses. If the problem remains, replace the following FRUs  one at a time to correct the problem.

  • Keyboard
  • Keyboard control card
  • System board

  • If a 00030100 error message appears,  power-off the computer and the external devices.  Then power-on the computer before you power-on the external devices.

1. Make sure the printer is correctly connected and is powered-on.
2. Run the printer self-test.

If the printer self-test does not run correctly, the problem is in the printer. Refer to the printer service manual.

If the printer self-test runs correctly, do the following.

1. Verify the port settings in configuration.
2. Install a wrap plug on the port (indicated in configuration)  and run the advanced diagnostic tests.
3. If the advanced diagnostic tests (with the wrap plug installed)  do not detect a failure, replace the printer cable. If the problem is not corrected, replace the system board.

• If the TrackPoint II  does not work, check the configuration.  If the configuration of the TrackPoint II is set to Disabled or Off, change it to Enable or On.

If the problem remains, continue.

NOTE: TrackPoint II automatically compensates to adjust  the pointer sensor. This causes the pointer to move slightly on  the screen and then stop. Pointer  movement might occur when  a slight, steady pressure is applied to the TrackPoint II pointer when  the computer is powered-on or running, or  when exceeded temperature range requires re-adjustment.

• If the cursor floats or moves erratically, power-off and disconnect the  mouse. Power-on the computer. If the  problem goes away, replace the mouse. If the problem remains, replace the  keyboard.- For click button or pointing stick problems:

  1. Go to the Easy-Setup screen.
  2. Select an item with the pointing stick.
  3. Press either left or right click button.
  4. Verify that both buttons work correctly.

  If the pointing stick or the click button does not work,  do the following.

  1. Reseat the keyboard cables.
  2. Replace the keyboard.
  3. Replace the interposer card (355x, 360x, 750x, 755x).
  4. Replace keyboard control card (720).
  5. Replace the system board.

Insert a coin between the diskette drive bezel and the computer as shown 1 and push the bezel from the bottom of the computer 2 to remove it.

Insert a coin between the diskette drive bezel and the computer as shown 1 and push the bezel from the bottom of the computer 2 to remove it.

The system status indicators show the current computer status in different colors (green, yellow, and orange).

Symbol Color Meaning

  Blinking green       Speaker sounds
                            (Does not sound for Models
                            355, 355Cs, 360, 360Cs and 370C)
 ---------------------------------------------------------------  

 Green                Battery fully charged
       Yellow               Battery usable
       Orange               Battery low
       Blinking orange      Battery almost depleted
       Blinking green,      Battery storage switch is set off
       yellow and orange
 ---------------------------------------------------------------  

  Green                Battery charging

  Orange               PC card in-use

  Orange               Diskette drive in-use

  Orange               Hard disk drive in-use

  Green                Keys in Num Lock mode

  Green                Keys in Caps Lock mode

  Green                Keys in Scroll Lock mode

  Green                Computer in suspend mode
       Blinking green       Computer resuming normal mode
 ---------------------------------------------------------------  

  Green                Computer powered on

Before checking problems with the computer, determine whether or not the damage applies to the warranty by referring to the following:

Note for Warranty:

During the warranty period, the customer may be responsible for repair costs if the damage was caused by misuse, accident, modification, unsuitable physical or operating environment, or improper maintenance by the customer.

The following list provides some common items that are not covered under warranty and some symptoms that could indicate that the system was subjected to stresses beyond normal use.

Warranty Coverage Notes

The following isnot covered under warranty:

• LCD panel cracked from being dropped or applying too much force.
• Scratched (cosmetic) parts.
• Cracked or broken plastic parts, broken  latches, broken pins  or connectors caused by excessive force.
• Damage caused by liquid spilled onto the system.
• Damage caused by improperly inserting a PCMCIA card or installation  of an incompatible card.
• Damage due to foreign material in the FDD or FDD bay.
• Damage to the diskette drive caused by pressing the  diskette drive cover or inserting diskettes with multiple labels.
• Diskette eject button was bent or damaged.
• Damage to the CD-ROM drive caused by excessive force shocked or dropped.
• Fuse blown by attaching non-supported device.
• Computer or hard disk could not be used  because the password was forgotten.

If the following symptoms are present, they could indicate the damage was caused by non-warranted activity:

• Missing parts can be a symptom of unauthorized service or  modification.
• HDD spindles can become noisy if subjected to  excessive force or is dropped.
• I9990303 errors can be caused by exposure to strong magnetic fields.

How to Use Error Messages

Use the error codes displayed on the screen to diagnose failures. If more than one error code is displayed, begin the diagnosis with the first error code.

The cause of the first error code can result in false error codes being displayed. If no error code is displayed, see if the error symptom is listed in the 'Symptom-to-FRU Index'

How to Diagnose Multiple FRUs

When the adapter or device has more than one FRU, the error code could be caused by either FRU. Before replacing multi-FRUs, try removing or exchanging each FRU, one by one in the designated sequence, to see if the symptoms change.

Depending on the model, the memory size that is available for customer use appears differently. This is not a hardware problem. See the following tables for the available memory size of each card.

NOTE: For Models 370C, 755C and 755Cs, one of two types of memory cards can be used, IC DRAM card or DIMM card. If DIMM cards are installed, replace IC DRAM with DIMM in the following.

IC DRAM	750, 750C, 750Cs, 750P	355x, 360x, 370C, 750Ce, 755C, 755Cs
0 MB	3904 KB	3712 KB
2 MB	5952 KB	5760 KB
4 MB	8000 KB	7808 KB
8 MB	12096 KB	11904 KB
16 MB	20288 KB	20096 KB

DIMM	370C, 755C, 755Cs
0 MB	3712 KB
4 MB	7808 KB
8 MB	11904 KB
12 MB	16000 KB
24 MB	28288 KB
16 MB	20096 KB
20 MB	24192 KB
32 MB	36480 KB

Memory errors might stop system operations, show error messages on the screen, or hang the system. The computer detects memory parity errors but does not correct them.

Use the following procedure to isolate memory problems.

Notes on Memory Errors

• For Models 355x, 360x, and 370C, ignore any references  to parity errors.
• DIMM Adapter and DIMM card are not supported for 355x and 360x.  Remove them (if installed).

1. Installing a non-parity memory card causes memory errors.  Before you go to the next procedure, check whether or not  the memory card use parity or non-parity. If the non-parity  memory card is installed, disable the parity check on Easy-Setup configuration screen.
2. Make sure that the memory card is fully installed  into the connector.  Loose connection can cause an error.
3. Power-off the computer and  remove the IC DRAM card, or DIMM card  from its slot (if installed).
4. Press and hold the F1 key, then power-on the computer.  Hold the F1 key down until Easy-Setup screen appears.
5. Select Test and press enter.
6. Select Memory and press enter to  run the memory test on base memory. If an error appears, replace the  system board.
7. Power-off the computer and reinstall the IC DRAM card,  then power-on the computer.  Verify the memory size, then test the memory.  If an error appears, replace the IC DRAM card.

If memory problems occur intermittently, use the loop option to repeat the test. When the test detects an error, an error log is printed on the printer connected to the parallel port. See 'Error Log' information.

If a parity error is logged in CMOS, POST error code 118 appears when the power is turned on. To clear the log and to test the memory, run the memory diagnostic. If no error is detected by the test, the log is cleared, and error code 118 will not appear the next time the POST is run. If the 118 error code occurs repeatedly, determine and replace the failing memory FRU. FRUs should not be replaced because of a single, un-reproducible failure. Single failures can occur from a variety of reasons that have nothing to do with a hardware defect such as: cosmic radiation, electrostatic discharge, or software errors. FRUs replacement should only be considered when a recurring problems exits. If this is suspected, clear the error log and run the test again. Do not replace any FRUs if log errors do not reappear.

System Programs in Flash Memory

System setup programs and diagnostic tests are stored in Flash memory.

Flash Memory Update

A flash memory update is required for the following conditions:

• New versions of system programs.
• New feature or options are added.

When Updating Flash Memory

  Do not power-off the computer, disconnect the Vac power, or remove the battery during the Flash update.

On certain systems, updating Flash memory can reset all customer‘s configuration settings to the default values.

To update the Flash memory, perform the following steps:

1. Connect the AC Adapter and install the battery pack.
2. Get the appropriate diskette which contains the update.
3. Insert the System Program Service Diskette into drive A and power-on the computer.
4. Select Update system programs from the menu.

System Board and Processor Card Checkout (370C, 750Ce, 755C, 755Cs)

The processing functions for the Models 370C, 750C, 755Ce, and 755Cs are performed by both the system board and the processor card. Processor problems can be caused by either FRU. However, the processor card generally has a lower probability of failure. When a numeric code calls the system board or the processor card as a FRU, or the processor card is called by a diagnostic test by showing FRU code 11, use the following procedure to isolate the problem.

1. Run the system board test to verify the symptom. This test verifies  both the system board and the processor card.  If no error is detected, return to 'General Checkout'
2. If FRU code 10 appears, replace the system board but do not replace  the processor card. Transfer the processor card from the old system  board to the new system board.
3. If FRU code 11 appears, reseat the processor card.
4. Rerun the test to verify the fix.
5. If FRU code 11 remains, replace the processor card.

If above procedure does not correct the problem, go to 'Undetermined Problems'

Pen and Digitizer Checkout (360P, 360PE, 750P)

To check the stylus pen and digitizer, do the following.

1. Press and hold the F1 key.- Power-on the computer to go to Easy-Setup screen.- Select Test by using the stylus pen.- If the test menu appears, the pen and digitizer  are operating correctly.- If the test menu does not appear, do the following.

      1. Do the 'Digitizer Adjustment' (described below)- If the problem remains, replace the stylus pen.- If the problem still remains after step 6 in the adjustment,
              replace the LCD assembly.
   

Digitizer Adjustment

Adjust the pen-point pressure when:

• The LCD is replaced with a new one.
• The LCD is changed to a pen LCD from a monochrome model.
• The stylus pen or digitizer is not working correctly.

Do the following:

1. Press and hold the F1 key, then power-on the computer  to go to the Easy-Setup menu.- Press Ctrl+P. The following Pen  icon appears on the screen.

   

   • Open the LCD all the way to 180 degrees. (Do not convert it into  the tablet-style notebook.)- Select the pen icon by moving the cursor on the  icon and clicking it.  Without applying any pressure on the screen,  hold the stylus pen so it stands on the screen,  then press Enter.

     NOTE: The pressure on the screen should only be from the weight of the stylus pen.

     • Restart the system.

If a device is installed but the icon appears in a gray shade rather than a dark shade on the basic diagnostics screen, the device is defective. Reseat the device connectors. If the symptom remains, replace the device or the system board. If needed, adjust the contrast control to clearly distinguish the shades of the icon.

If a device that is not installed appears in a dark shade, do the following.

1. Replace the first device, such as a FDD, HDD, or PCMCIA.
2. If the problem remains, replace the system board.

PCMCIA, Parallel, and Serial icons are always displayed in dark shade, because the icons represent subsystems of the system board and not attachment of the devices.

If a device is installed but the icon appears in a gray shade rather than a dark shade on the basic diagnostics screen, the device is defective. Reseat the device connectors. If the symptom remains, replace the device or the system board. If needed, adjust the contrast control to clearly distinguish the shades of the icon.

If a device that is not installed appears in a dark shade, for example, FDD-2 appears in a dark shade when NO second FDD is installed, do the following.

1. Replace the first device, such as a FDD-1, HDD-1, or PCMCIA-1.
2. If the problem remains, replace the system board.

PCMCIA-1, Parallel, and Serial icons are always displayed in dark shade, because the icons represent subsystems of the system board and not attachment of the devices.

The HDD-1, FDD-1, or PCMCIA-1 represents the first drive in the system configuration, respectively. Similarly, the HDD-2, FDD-2, or PCMCIA-2 represents the second drive, usually attached through a port replicator or an expansion unit.

The TFT LCD of the notebook computers contain over 921000 thin film transistors (TFTs). A small number of missing, discolored or lighted dots (on all the time) is characteristic of TFT LCD technology. Excessive pixel problems can cause viewing concerns. The LCDshould be replaced if the number of missing or discolored, or lighted dots in any colored background is 21 or more****

Symptom/Error	FRU/Action
No beep, power-on indicator on, and a blank LCD during POST.	1. System Board 2. DC/DC Card 3. Processor Card (370C, 750Ce, 755C, and 755Cs)
° LCD backlight not working, or ° LCD too dark, or ° LCD brightness cannot be adjusted, or ° LCD contrast cannot be adjusted.	1. Reseat the LCD connectors. 2. LCD Assembly 3. Interposer Card 4. DC/DC Card
° LCD screen unreadable, or ° Characters missing pels, or ° Screen abnormal, or ° Wrong color displayed.	1. See the preceding important note. 2. Reseat the all LCD connectors 3. LCD Assembly 4. System Board 5. Interposer Card
LCD has extra horizontal or vertical lines displayed.	1. LCD Assembly

Symptom/Error	FRU/Action
Indicator incorrectly remains off or on, but system runs correctly.	1. Reseat the status indicator cable. 2. Status Indicator 3. Interposer Card 4. System Board
Battery power status indicator blinks from green, yellow, to orange.	1. Check that a correct battery is installed. 2. Set the battery storage switch to ON. 3. Battery Pack 4. DC/DC Card 5. System Board

Symptom/Error	FRU/Action
External display does not work correctly.	1. See 'External Display Self-Test' in: 'External Devices Checkout'
Printer problems.	1. Run Printer Self-test 2. System Board 3. Parallel Port Device 4. Cable
Serial or parallel port device problems.	1. Device 2. Device Cable 3. System Board

Symptom/Error	FRU/Action
Stylus pen or digitizer does not work correctly.	1. Go to 'Pen and Digitizer Checkout' (360P, 360PE, 750P)
Errors occur only when Port Replicator is used.	1. See 'Port Replicator Checkout' in 'Common Devices Checkout'
PCMCIA slot pin is damaged.	1. PCMCIA Slots Assembly

NOTE: If you cannot find a symptom or error in this list and the problem remains, see 'Undetermined Problems'

You are here because the diagnostic tests did not identify which adapter or device failed, installed devices are incorrect, a short circuit is suspected, or the system is inoperative. Follow the procedures below to isolate the failing FRU (do not isolate non-defective FRUs).

Verify that all attached devices are supported by the computers.

Verify that the power supply being used at the time of the failure is operating correctly.

(See 'Power Systems Checkout')

1. Power-off the computer.- Check the cables, wires, and connectors for  short circuits and open circuits. Visually check them for damage.  If any problems are found, replace the FRU.- Remove or disconnect all of the following devices.

   1. Non-IBM devices- Devices attached to the expansion bus connector- Printer, mouse, and other external devices- Battery pack- Hard disk drive- Diskette drive or the device attached to the diskette drive  connector- IC DRAM card or DIMM card- PC cards

      .
      174            **NOTE:**
                   Remember that removing the hard disk drive, an IC DRAM card,
                   or any adapter or device, might cause configuration errors.
                   Ignore error code 

   • Power-on the computer.- Determine if the problem has changed.- If the problem does not occur again,  reconnect the removed devices one  at a time until you find the failing FRU.- If the problem remains, replace the following FRUs one at a time.  Do not replace a non-defective FRU.

        - DC/DC card- Audio card- Interposer card- LCD assembly- System board- Processor card (370C, 750Ce, 755C, and 755Cs)
     

Diagnostic errors are printed on the printer that is attached to the parallel port when the error is detected. The error is also logged in the system memory.

Do the following procedure to display the errors.

1. End the test, if it is running.
2. Press Ctrl+A to select the advanced diagnostic mode.
3. Press Ctrl+E .
4. The error log appears.
5. To exit the screen, select the cancel icon or press Esc.

The error log is not saved when system power is powered-off.

Do the following to format the hard disk.

  Make sure the drive address to be formatted is correct. This procedure will erase all information on the disk.

1. Power-off the computer.- Insert the ThinkPad 750Ce hardware maintenance diskette  into diskette drive A and power-on the computer.

   NOTE:   You can use this maintenance diskette for all Models.

   • Select Format the hard disk from the main menu.
   • Select the drive from the menu.
   • Follow the instructions on the screen.

The following table shows the Fn key and function key combinations and their corresponding functions.

The Fn key works independently from the operating system. The operating system obtains the status through the system management interface to control the system.

Fn +	Description
F1	Reserved
F2	Fuel-gauge display ON/OFF
F3	Standby mode invocation
F4	Suspend mode invocation
F5	Audio volume Down
F6	Audio volume UP
F7	LCD/CRT display switching
F8	LCD normal/reverse switching
F9	Reserved
F10	Reserved
F11	Power management mode switching (Toggles High power, Intelligent, Economy)
F12	Hibernation invocation

Each time you press the Function key  
one of the following messages (called On-Screen Message) appears at the top left corner of the LCD.

The changed values are automatically saved when you return to the TV Channel On-Screen message. The values are not saved when you power-off the TV Tuner without returning to this message.

Message on       Parameter
 LCD
                   TV Channel
  (xx)             By using <- and +>  you can select the channels
                   from 2 to 69.
                   Color Adjustment
   COL             By pressing and holding <- or +>
                   you can change the color.
                   TINT Adjustment
   TNT             By pressing and holding <- or +>
                   you can change the tint.
                   Bright Adjustment
   BRT             By pressing and holding <- or +>
                   you can change the brightness.
                   Contrast Adjustment
   CNT             By pressing and holding <- or +>
                   you can change the contrast.
   ---             (No function)
                    Reserved.
                   Auto Tune Sensitivity Selection
    LO             LO: Means the sensitivity
                   of the TV is low.  In this mode, the TV Tuner receives
                   strong TV signals only.  To set LO,
                   press <-
    HI             HI: Means the sensitivity
                   of the TV is high (factory default).
                   In this mode, the TV Tuner receives weak and strong TV signals.
                   To set HI, press +>
    D3S            Time On-Screen Message appears
                   D3S: On-screen Message appears for 3 seconds.
                   To set D3S, press <-
    DON            DON: On-screen Message always appears.
                   To set DON press +>

The following table shows what to do to solve problems when the TV Tuner does not work correctly.

Problem        Probable Cause
 The TV Tuner        ° Computer is not powered on.
 does not operate.   ° Computer is in suspend mode.
  (No picture        ° Volume control of the TV Tuner or computer
   or sound)           is not adjusted correctly.
                     ° The power for the TV Tuner is not supplied.
                       (See Power-on the TV Tuner)
                     ° The wall outlet from the outdoor antenna is not active.
                     ° The video or antenna cable is not connected correctly.
                     ° Antenna elements of the active antenna unit are not adjusted.
                     ° The batteries in the active antenna unit are not inserted
                       correctly.
                     ° The batteries in the active antenna unit are depleted.
                     ° The TV Tuner is not set up correctly.
                     ° You cannot watch TV or videos on the external display.
                     ° LO is set for the auto tune sensitivity
                       selection.
 No color.           ° The program is not in color.

Snow and noise      ° Switch the TV/EXT (  ) button.
 only.
 Pictures are out    For TV:
 of shape, or have   ° The channel is not tuned correctly.
 double images.      ° Adjust the antenna.
                     For VCR:
                     ° Change the tracking adjustment.
 Dotted lines        ° Usually caused by interference from
 or stripes.           neon signs, hair dryers, and so on.
                       Move the computer to avoid the interference.
 Picture control     ° Do not power-off the TV Tuner
 are not saved.        when adjusting functions such as picture control,
                       color, tint, brightness, or contrast.
 Channel number is   ° Select your favorite mode for the on-screen message.
 always displayed or
 is not displayed.

What to Do First Passwords Port Replicator Problems

Service for U. S. and Canada

In the U. S. and Canada, the ThinkPad 370C and ThinkPad 360PE are serviced only through EasyServe.

This hardware maintenance manual covers information about the following IBM ThinkPad models

• 355, 360, 750 (monochrome)
• 355C, 360C, 360CE, 370C, 750C, 755C (TFT color)
• 750Ce (TFT color, enhanced)
• 355Cs, 360Cs, 360CSE, 750Cs, 755Cs (STN color)
• 360P, 360PE, 750P (pen).

When information affects only a specific model, the model number is shown in parenthesis in the heading or is explained in the text. Before you go to the checkout guide, be sure to read this section.

• Be extremely careful during write operations  such as copying, saving, or formatting. Drives in the computer that you are servicing  might have been rearranged or the drive startup  sequence might have been altered.  If you select an incorrect drive,  data or programs can be written over.
• Replace FRUs only for the correct model.
• When you replace the FRU, make sure the model of the machine  and FRU part number are correct by referring to the part list.
• FRUs should not be replaced because of a single, un-reproducible  failure. Single failures can occur from a variety of reasons  that have nothing to do with a hardware defect such as:  cosmic radiation, electrostatic discharge, or software errors.  FRU replacement should only be considered when  a recurring problem exists.  If this is suspected, clear the error log and run the test again. Do not replace any FRUs if log errors do not reappear.

The servicer must include the following in the parts exchange form or part return form that is attached to the returned FRU.

1. Name and phone number of servicer.
2. Date of service.
3. Date when part failed.
4. Date of purchase.
5. Failure symptoms, error codes appearing on display,  and beep symptoms.
6. Procedure index and page number in which failing FRU was detected.
7. Failing FRU name and part number.
8. Machine type, model number, and serial number.
9. Customer's name and address.

GERMAN Preload Sample for 9545-370C

CONFIG.SYS

DEVICE=C:\DOS\HIMEM.SYS
 DOS=HIGH,UMB
 FILES=30
 BUFFERS=10
 STACKS=9,256
 DEVICE=C:\DOS\EMM386.EXE NOEMS I=B000-B7FF X=C800-CFFF I=E000-E5FF
 DEVICEHIGH=C:\THINKPAD\IBMDSS01.SYS
 DEVICEHIGH=C:\THINKPAD\IBMDOSCS.SYS
 DEVICEHIGH=C:\THINKPAD\DICRMU01.SYS /MA=C800-CFFF
 DEVICEHIGH=C:\THINKPAD\$ICPMDOS.SYS
 DEVICEHIGH=C:\DOS\POWER.EXE
 DEVICEHIGH=C:\THINKPAD\AUTODRV.SYS C:\THINKPAD\AUTODRV.INI
 DEVICEHIGH=C:\DOS\SETVER.EXE
 DEVICE=C:\IBMVESA\VESA.EXE
 DEVICEHIGH=C:\DOS\DISPLAY.SYS CON=(,,1)
 COUNTRY=049,850,C:\DOS\COUNTRY.SYS
 REM UN'REM' the following line for PCMCIA ATA card support
 REM DEVICEHIGH=C:\THINKPAD\DISKDRV.SYS
 REM UN'REM' the following line for external keyboard support
 REM DEVICEHIGH=C:\$IBMHIPD.SYS

AUTOEXEC.BAT

@ECHO OFF
 PROMPT $p$g
 PATH=C:\;C:\DOS;C:\WINDOWS;C:\THINKPAD;C:\ASYMPRES;C:\CCMOBILE;
 SET TEMP=C:\WINDOWS\TEMP
 SET WIN$=C:\WINDOWS
 SET IBMAV=C:\DOS
 SET IPF_PATH=C:\IPFWIN
 C:\DOS\MODE.COM CON CP PREP=((850) C:\DOS\EGA.CPI)
 C:\DOS\MODE.COM CON CP SEL=850
 LOADHIGH C:\DOS\KEYB.COM GR,,C:\DOS\KEYBOARD.SYS /ID:129
 REM Zeile für automatische Dateiverwaltung im Hibernationsmodus
 C:\THINKPAD\PS2 HFILE C
 LOADHIGH C:\DOS\MOUSE.COM /Y
 REM to disable write-caching, remove '+' from the following line
 REM LOADHIGH C:\DOS\SMARTDRV.EXE  C+
 LOADHIGH C:\DOS\DOSKEY.COM
 LOADHIGH C:\DOS\SHARE.EXE
 LOADHIGH C:\THINKPAD\FUEL DOS.COM
 CALL C:\DOS\IBMAVDR.BAT C:\DOS\
 WIN

  Passwords - Reset Pushbutton

The Pass words are security features that are used to protect the system and the hard disk data from unauthorized access.

There are three types of passwords as follows:

• Power-on Password (POP)
• Hard disk Password (HDP)
• Supervisor Password (Privileged Access Password, PAP)

No overriding is provided. Obtaining permission from the password owner to unlock the password is a prerequisite for running diagnostic tests and performing maintenance service.

See 'Password Combinations' for more information about passwords.

How to Disable the Power-On Password:

1. Power-off the computer.- Open the keyboard and remove the battery pack and the diskette  drive.- Remove the attachment holder.

   • For Models 355x and 360x, see >> '1115 Standby Battery'
   • For Models 370C, 750x, 755C, and 755Cs, see >> '2105 Standby Battery'

   • Install a jumper on the power-on password connector -1- at  bottom left side of the system board.

     

     • Reinstall the diskette drive and the battery pack.
     • Power-on the computer and wait until the POST ends.
     • Verify that the password prompt does not appear.
     • After the service check is completed, remove the jumper.

To reactivate the password, set the password again.

Reset Pushbutton

The reset pushbutton resets the system regardless of the microcode status and forces power to be powered-off.

Use this pushbutton to power-off when power is not completely off or the microcode is in a hung state. See 'System Board (Top View)' for the location of the pushbutton.

Parts Catalog - FRU P/N

• IBM 2619 / 2620 Models 355x 360x
• IBM 9545 Models 370C
• IBM 9545 Models 750x
• IBM 9545 Models 755C 755Cs
• ThinkPad
• Common / Option
• Parts Catalog
• ThinkPad Common Devices List

  Password Combinations

The password relationship is:

• When POP is the same as HDP

The POP prompt appears, but the HDP prompt does not appear.

• When POP is not the same as HDP

  Both POP and HDP prompts appear.

  • PAP and HDP

  When PAP is used, the HDP is enabled automatically, but no HDP prompt  appears. The HDP is set the same as PAP.

1. Power Switch- Modem Card Connector (355x, 360x)- Serial Connector- Audio Card Connector- Speaker Connector (370C only)- Parallel Connector- Interposer Card Connector- External Display Connector- Reset Pushbutton- System Expansion Connector

                  Model 355x does not have this connector.
                - External Input Device Connector- Hard Disk Drive Connector- PCMCIA Slot- DC / DC Card Connector- IC DRAM Card Connector- Diskette Drive Connector
   

 

• Two types of LCDs are available for the Model 755C: one with a contrast control  and one without. Make sure that you replace the LCD with the correct type.
• The LCD for the Model 370C does not have a contrast control.

1 When replacing the LCD ground-terminal screw, do not pull or push the LCD cables.

2 When removing the LCD cables, pull the connector straight up. Incorrect handling can damage the connector.

NOTE: For the color models, make sure the indicator does not catch the right LCD connector when replacing the status indicator.

3 Remove the screw.

4 Remove the right hinge cover.

5 When removing the left hinge cover, use a small screwdriver as shown to release the latch from the rear base cover. Pull the hinge cover slightly upward to keep it unlatched.

6 From the front side, remove the latch with a small screwdriver as shown to remove the cover. Be careful not to scratch the surface of the computer when you use a screwdriver to remove the latches.

7 Remove the four screws.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	LCD ground-terminal (1)	4 mm
3	LCD hinge cover, right (1)	4 mm
7	LCD hinge (4)	4 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

  pleaseREAD**** - see >>

Caring for the LCD

• When cleaning of the LCD becomes necessary,  gently wipe the LCD with a dry, soft cloth.  Do not use alcohol or detergent to clean the LCD.
• To avoid damaging the LCD,  do not scratch or apply any force to its surface.
• Do not put anything on the surface of the LCD.

1. Diskette Drive Cover- Power Switch- Microphone/Line-In Jack- Headphone Jack

     Not all models have jacks
    **3** and **4**.
   
    - Power Jack- Serial Connector- Parallel Connector- External Display Connector- Reset Pushbutton- System Expansion Connector
   

Model 355x does not have this connector.

A multimedia portable expansion unit, port replicator, or port replicator with PCMCIA can be connected to this interface to support the following features.

• 16-bit AT-bus interface
• Serial port
• Parallel port
• Keyboard and mouse
• HDD connection
• LED control signals
• Visual signals
• Audio signals
• FDD signals
• PCMCIA signals
• Power controls
• Power line

11 Connector Door

12 Rear Door

1. Power-On Password Connector
2. Backup Battery Connector
3. Standby Battery Connector
4. IC DRAM Card Connector
5. Processor Card Connector (750Ce, 755C, 755Cs)

1. System Board Connector

DC/DC Card - Top View

1. External Power Jack
2. Battery Pack Terminal

Models 355x, 360x

Models 370C, 750x, 755x

1. LCD Connector, Color
2. LCD Connector, Pen
3. LCD Connector, Monochrome and Color
4. LCD Power Connector, Color
5. Status Indicator Connector
6. Keyboard TrackPoint II Connector
7. Keyboard Signal Connector
8. Keyboard Signal Connector
9. LCD Open Detect Switch

Miscellaneous Parts.

	FRU P/N
AC Adapter (35 W, 3-pin)	85G1952
For Japan (2-pin)	85G6669
AC Adapter (40 W, 3-pin)	49G2196
For Japan (2-pin)	49G2197
AC Adapter (40 W, 3-pin, U.S. only)
(not for 370C)	84G4320
Foot (right or left)	84G4326
Miscellaneous Parts Kit
(Includes DC-in holder, spacer, warning label)
For Models 750x	66G5039
For Models 355x, 360x, 370C, 755C, 755Cs	84G2254
PC Card Locking Bar	85G8625
Screw Kit	66G5124
Includes:
10-2.5 x 4 mm, 10-2.5 x 6 mm
10-2.5 x 8 mm, Flat head
10-2.5 x 8 mm, 10-2.5 x 16 mm
10-hex stud I/O, 10-hex stud bus
2-washer for hex stud bus)
IC DRAM CARD - Eject Tape	53G9318
ThinkPad 370C/755 Memory
DIMM Memory Module Adapter
(OPT P/N TOMMADP)	84G4322
4MB DIMM Module (OPT P/N TOMMD04)	84G4323
8MB DIMM Module (OPT P/N TOMMD08)	84G6545
16MB DIMM Module (OPT P/N TOMMD16)	85G0193
	84G4324

1. When you replace the AC adapter or the Quick Charger with a new one, use the one for the country you are in even if the system is from different country.
2. The warranty for the system unit is not applied to all options.

Options

	FRU P/N
Audio Cable	66G5180
Car Battery Adapter
label sealed)48G9203(	49G1148
Car Battery Adapter
label sealed)66G9984(	84G4359
Diskette Drive Attachment Unit	66G5069
IC DRAM CARD 2MB	07G1414
IC DRAM CARD 4MB	07G1415
IC DRAM CARD 8MB	07G1416
IC DRAM CARD 16MB	66G0094
Microphone	66G7871
PS/2 Miniature Mouse	95F5723
Port Replicator
(Model-II 760/765/765L)	66G3575
Port Replicator with PCMCIA
(Model-I 760/765/765L)	66G3574
Quick Charger (3-pin)	66G2815
For Japan (2-pin)	66G2816

Model Unique Options

Models 355x, 360x, 370C

	FRU P/N
4MB IC DRAM CARD (no parity)	84G5724
8MB Basic IC DRAM CARD (no parity)	84G5725
16MB IC DRAM CARD (no parity)	84G5726
Internal Modem Card
(U.S./Canada/Latin America)	84G5917
Telephone Cable
(U.S./Canada/Latin America)	84G8254
Telephone Wall Plug	85G2367

Model 370C

	FRU P/N
Audio Card	66G5037
4MB IC DRAM CARD (no parity)	84G5724
8MB Basic IC DRAM CARD (no parity)	84G5725
16MB IC DRAM CARD (no parity	84G5726
Diskette Drive (4-mode)
Supported in U.S. only.	66G5060

Model 750x

	FRU P/N
AC Adapter (35 W, 3-pin)	85G1952
For Japan (2-pin)	85G6669
AC Adapter (40 W, 3-pin, U.S. only)	84G4320
AC Adapter (40 W, 3-pin)	49G2196
For Japan (2-pin)	49G2197

Model 755C, 755Cs

	FRU P/N
DIMM 4MB	84G4323
DIMM 8MB	84G6545
DIMM 16MB	84G4324
DIMM Adapter Card	84G4322
Diskette Drive (4-mode)
Supported in U.S. only.	66G5060

Numeric Keypad

	FRU P/N
Belgian	95F5741
Canadian French	95F5466
Danish	95F5467
Dutch	95F5467
French	95F6313
German	95F6314
Greek	95F5467
Hebrew	95F5741
Icelandic	95F5467
Italian	95F6316
Japanese	79F6401
Norwegian	95F5467
Spanish	95F6315
Swedish/Finnish	95F5468
Swiss/French	95F5711
Swiss/German	95F5715
Turkish	95F5467
U.K. English	95F5741
U.S. English	95F5741

Accessories

	FRU P/N
Keyboard/Mouse Cable	54G0444

Tools

	FRU P/N
Tri-Connector Wrap Plug	72X8546
PC Test Card	35G4703
Screwdriver Kit	95F3598
ThinkPad 750Ce	82G3891
Hardware Maintenance Diskette
(This diskette is common for
all models of ThinkPad.)

Power Cords

 

  Use the power cordcertified for your country.****

Ref.	Country	30/40W	35W
1	Colombia, U.S., Venezuela	13F9959	25H2207
1	Japan, 2-pin	6454377	85G6665
1	Japan, 3-pin	65F0031
2	Hong Kong, Singapore, U.K.	14F0033	25H2215
3	France, Germany, Spain	13F9979	25H2209
4	Italy	14F0069	25H2223
5	Australia, New Zealand	13F9940	25H2205
6	Denmark	13F9997	25H2211
7	Israel	14F0087	25H2225
8	Bangladesh, Pakistan, Sri Lanka, South Africa	14F0015	25H2213
9	Switzerland	14F0051	25H2221
10	Thailand	1838574	25H2219

NOTE:

• Models 370C, 755C, and 755Cs do not support the  30W AC adapter.
• The 30/40W cord is 1.8m (6 ft.) long, the 35W cord is 0.15m (6-Inch).

Use the chart to match the size and shape of the screws in the computer you are servicing.

Remove the center latch 1, then remove the rear connector door by flexing it 2

To replace the foot:

• Align the foot in the open position with one  pivot in its hinge in the base cover
• Press the other pivot point into position with your thumb or finger

1. Do not apply any extra force to  the hard disk drive when removing it. Remove the hard disk drive exactly as shown in the figure.
2. Do not drop or apply any shock to the hard disk drive. The hard disk drive is sensitive to physical shock.  Incorrect handling can damage it or  cause permanent loss of data.  Before removing the hard disk drive, have  the user make a backup copy of all information on the hard disk.  Never remove the hard disk drive while the system is operating or is in  suspend mode.

After replacing the hard disk drive, latch the removal strap into the correct position.

 
) must be used to remove the card. 53G9318 The IC DRAM card is sensitive to physical shock. Incorrect handling of the card can damage it. The eject tape ( P/N

1 When replacing the LCD ground-terminal screw, do not pull or push the LCD cables.

2 When removing the LCD cables, pull the connector straight up. Incorrect handling can damage the connector.

NOTE: For the color model, make sure the indicator does not hook the most right LCD connector when replacing the status indicator.

3 Remove the screw.

4 Remove the right hinge cover.

5 When removing the left hinge cover, use a small screwdriver as shown to release the latch from the rear base cover. Pull the hinge cover slightly upward to keep it unlatched.

6 From the front side, remove the latch with a small screwdriver as shown to remove the cover. Be careful not to scratch the surface of the computer when you use a screwdriver to remove the latches.

7 Remove the four screws.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	LCD ground-terminal (1)	4 mm
3	LCD hinge cover, right (1)	4 mm
7	LCD hinge (4)	4 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

  pleaseREAD**** - see >>

Caring for the LCD

• When cleaning of the LCD becomes necessary,  gently wipe the LCD with a dry, soft cloth.  Do not use alcohol or detergent to clean the LCD.
• To avoid damage to the LCD,  do not scratch or apply any force to its surface.
• Do not put anything on the surface of the LCD.

1095 Interposer Card

 
Carefully remove any metal particles that might have flaked off. Be careful not to damage it with a screwdrivers, screws, or other objects.

2 When replacing the speaker shield, insert it under the projection at the left, rear corner of the computer base.

NOTE: The shaded part in the figure is attached to the speaker shield assembly with light adhesive. This is a separate FRU from the speaker shield assembly.

3 When raising the speaker shield assembly, make sure that the shield assembly does not hook the three flexible cables of the keyboard.

For Model 360, gently raise the speaker shield assembly to avoid damaging the speaker cable. (For Models 355 and 355Cs, skip step 3, the speaker cable has already been removed.)

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1a	Speaker shield (1)	4 mm
1b	Hard disk drive connector (2)	6 mm
1c	System board (1)	16 mm
1d	System board, spacer (1)	16 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

Verify that the spacer 1d is in the correct position.

2 is a shield for radio frequency interference.

  The EEPROM on the system board contains the vital product data (VPD), that is, system unit serial number, system board serial number, and other computer unique data. When the system board is replaced, the system unit serial number must also be restored. Use the Set system identification* utility on the maintenance diskette to restore the number.

Do not power-off the computer when restoring the VPD.

The serial number label is attached to the bottom cover.

NOTE:

1. Before removing and replacing the system board, make sure that the  PCMCIA  cards are removed and the eject levers are not sticking out.
2. When replacing  the system board assembly, align the power-key slide  hub with the power-switch actuator by moving the power-key in  the direction of the arrow.  See the large circle in the figure.  Before tightening  any screws, check that the power-switch operates correctly.
3. Do not pull the PCMCIA slot assembly while removing the system board.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	Hinge bracket (4)	4 mm
2	Base cover, lower shield (1)	4 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

 
The system board can be damaged if the lower shield touches the system board components. Carefully follow the next instruction.

In step 4, gradually raise the system board from the lower shield until all the components of the system board just clear the tabs of the lower shield. Be careful not to raise it too far. While keeping the clearance to a minimum, separate the system board from the lower shield by moving the system board straight forward as shown by step 2

NOTE:

1. When handling the PCMCIA slot assembly,  be careful not to disassemble any part of it.  The slot assembly is not solidly fixed when it is removed from the  system board or the FRU.
2. The screw stand-off located each corner of  the PCMCIA slot, is easy to remove.  Make sure that the screw stand-off is positioned when replacing  the slot. Do not replace the slot without the screw stand.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	PCMCIA slot, upper (2)	12 mm
2	PCMCIA slot, lower (2)	14 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

Remove the center latch 1, then remove the rear connector door by flexing it 2.

To replace the foot:

• Align the foot in the open position with one  pivot in its hinge in the base cover
• Press the other pivot point into position with your thumb or finger

 

1. Do not apply any extra force to the  hard disk drive when removing it. Remove the hard disk drive exactly as shown in the figure.
2. Do not drop or apply any shock to the hard disk drive. The hard disk drive is sensitive to physical shock.  Incorrect handling can cause damage it,  and cause permanent loss of data on the hard disk.  Before removing the hard disk drive, have  the user make a  backup copy of all the information on the hard disk.  Never remove the hard disk drive while the system is operating or is in  suspend mode.

After replacing the hard disk drive, latch the removal strap into the correct position.

For Models 370C, 755C and 755Cs, one of two types of memory card can be used, IC DRAM card or DIMM card.

 
) must be used to remove the card. 53G9318 The IC DRAM card is sensitive to physical shock. Incorrect handling of the card can damage it. The eject tape ( P/N

NOTE: For Models 370C, 755C and 755Cs, one of the following combinations occupies the slot depending on the configuration.

• IC DRAM card + IC DRAM card base
• DIMMs on DIMM adapter

Press both locks at the same time and remove the DIMM.

While holding the strap 1, pull the DIMM adapter toward the front 2 to remove it.

NOTE:

1. If the IC DRAM cards or the DIMM are not installed and  the base plate is installed instead of these card,  remove the plate as follows:
2. Pinch the projection 1 on the left side of the plate,  then pull the plate slightly toward the front 2.- Raise the rear portion of the plate 3 and remove it.

   ![c78dc800](/static/parts/img/a2a0eeab1454.gif)- When inserting the DIMM into either connector
   

   on the DIMM adapter: 1. Locate the triangle A on the right side of the  socket.- With the notched end of the DIMM B toward the triangle,  insert the DIMM into the socket.- Pivot the DIMM until it snaps into place.

       If you have another DIMM to install, insert it in the
        other socket the same way.
   
       ![c78nra55](/static/parts/img/9c0111ce39da.gif)
   

2080 Speaker Shield Assembly

Models 750x, 755C, and 755Cs

and Model 370C

 

1. Carefully remove any metal particles that might have flaked off.
2. The shaded part in the figure is attached  to the speaker shield assembly  with light adhesive. This FRU is a separate FRU  from the speaker shield assembly.

1 Remove the screws.

2 Gently raise the speaker shield assembly to avoid damaging the speaker cable and make sure that the shield assembly does not hook the three flexible cables of the keyboard.

3 Disconnect the speaker connector.

When Disconnecting the Connector

• Do not pull the speaker cable before the audio card is removed.
• Be careful not to damage the speaker with screwdrivers, screws,  or other objects. A scratch will damage the speaker.
• When replacing the speaker shield, insert it  under the projection at the left, rear corner of the computer base.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1a	Speaker shield (4)	4 mm
1b	Hard disk drive connector (2)	6 mm
1c	System board (1)	16 mm
1d	System board, spacer (1)	16 mm
1e	Diskette drive connector (2)	6 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

1d shows the correct position of the spacer.

2 is a shield for radio frequency interference.

  The EEPROM on the system board contains the vital product data (VPD), that is, system unit serial number, system board serial number, and other computer unique data. When the system board is replaced, the system unit serial number must also be restored. Use the Set system identification* utility on the maintenance diskette to restore the number.

Do not power-off the computer when restoring the VPD.

The serial number label is attached to the bottom cover.

NOTE:

1. For Model 755C, there are two types the system boards.  Make sure the correct system board by checking the part number  in the part list.  After replacing the system board, run the display test  from the Easy-Setup and  use the Pause button to check the color graduations  that are displayed after the Video Page screen.  If the color blocks in one column are all the same color,  replace the system board.
2. Before removing and replacing the system board, make sure that the  PCMCIA  cards are removed and the eject levers are not sticking out.
3. When replacing  the system board assembly, align the power-key slide  hub with the power-switch actuator by moving the power-key in  the direction of the arrow.  See the large circle in the figure.  Before tightening  any screws, check that the power-switch operates correctly.
4. Do not pull the PCMCIA slot assembly while removing the system board.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	Hinge bracket (4)	4 mm
2	Base cover, lower shield (1)	4 mm

NOTE: Make sure you use the correct screw. Screw Size Chart

 
The system board can be damaged if the lower shield touches the system board components. Carefully follow the next instruction.

In step 3, gradually raise the system board from the lower shield until all components of the system board just clear the tabs of the lower shield. Be careful not to raise it too far. While keeping the clearance to a minimum, separate the system board from the lower shield by moving the system board straight forward as shown by step 3

NOTE: In step 1, each screw has a flat washer and a lock washer. When reinstalling the screws, make sure that the lock washer is placed next to the head of the screw. Incorrect washer placement can cause metal to flake.

Turn the system board upside down. Remove the screws 4 and 5. Models 370C, 755C and 755Cs have only the screw on the right side in step 5.

1. In step 1 , use 5.0 mm and 5.5 mm hex head screwdrivers.  To remove the processor card, gently lift  the area shown by 3 straight up.  Do not pull the other areas.
2. In step 6 , pull both edges of the bracket at the same time.  Do not pull the center of the bracket.

Use the following table for reference when replacing parts.

Step	Location (Quantity)	Length
1	Expansion bus, lower shield (2)	Hex head
1	I/O connector, lower shield (6)	Hex head
4	Processor card (1)	6 mm
5	Processor card connector 750x - (2), 370C, 755C, 755Cs - (1)	4 mm

NOTE: Make sure you use the correct screw. Screw Size Chart