ThinkPad 750 / 755 (and 370C)

13 variants of this machine type, side by side. A cell spanning several columns is shared by those models, so the narrow cells are the differences — memory type, battery chemistry and panel are what usually change across a range.

IBM model codes — 169 models of machine type 9545

Variant	Model codes
ThinkPad 755CD	9545-CD6, 9545-CD7, 9545-F3K, 9545-F3L, 9545-FBK, 9545-FBL, 9545-FFK, 9545-FFL, 9545-FHK, 9545-FHL, 9545-FNK, 9545-FNL, 9545-FPK, 9545-FPL, 9545-FQK, 9545-FQL
ThinkPad 755CX	9545-CX3, 9545-H3L, 9545-HBL, 9545-HDL, 9545-HFL, 9545-HHL, 9545-HNL, 9545-HPL, 9545-HQL
ThinkPad 755CV	9545-CV5, 9545-CV6, 9545-EBK, 9545-EBL, 9545-ENK, 9545-ENL, 9545-EPK, 9545-EPL
ThinkPad 755CDV	9545-DV5, 9545-DV6, 9545-G3K, 9545-G3L, 9545-GBK, 9545-GBL, 9545-GFK, 9545-GFL, 9545-GNK, 9545-GNL, 9545-GPK, 9545-GPL
Variant not recorded	9545-6BC, 9545-6BD, 9545-6BE, 9545-750, 9545-7BC, 9545-7BD, 9545-7BE, 9545-7DD, 9545-7NC, 9545-7ND, 9545-7NE, 9545-7PC, 9545-7PD, 9545-7PE, 9545-8BJ, 9545-8NJ, 9545-8PK, 9545-9BD, 9545-9BE, 9545-9ND, 9545-9NE, 9545-9PD, 9545-9PE, 9545-A3K, 9545-ABJ, 9545-ABK, 9545-AFK, 9545-ANJ, 9545-ANK, 9545-APJ, 9545-APK, 9545-CD3, 9545-CD4, 9545-CE2, 9545-CE3, 9545-CE4, 9545-CV1, 9545-CV2, 9545-CX1, 9545-CX2, 9545-CX4, 9545-CX5, 9545-CX6, 9545-DS1, 9545-DS2, 9545-DS5, 9545-DS6, 9545-DV1, 9545-DV2, 9545-DV3, 9545-ECE, 9545-EOC, 9545-EOE, 9545-EOG, 9545-EYC, 9545-EYE, 9545-F3C, 9545-F3E, 9545-FJ6, 9545-FJ8, 9545-FJA, 9545-FMC, 9545-FME, 9545-FOC, 9545-FOE, 9545-FOG, 9545-FYC, 9545-FYE, 9545-FZE, 9545-H3E, 9545-HBD, 9545-HBE, 9545-HFE, 9545-HNE, 9545-KOC, 9545-KOE, 9545-KZC, 9545-KZE, 9545-KZG, 9545-LCE, 9545-LJC, 9545-LJE, 9545-LJG, 9545-LJK, 9545-LJM, 9545-LOC, 9545-LOE, 9545-LOG, 9545-LYE, 9545-LYG, 9545-LZC, 9545-LZE, 9545-LZG, 9545-Q3D, 9545-QDD, 9545-QFC, 9545-QFD, 9545-QFJ, 9545-QHC, 9545-QHD, 9545-QNC, 9545-QND, 9545-QNE, 9545-QPC, 9545-QPD, 9545-QQC, 9545-QQD, 9545-S3J, 9545-S3K, 9545-SBJ, 9545-SBK, 9545-SDJ, 9545-SFJ, 9545-SFK, 9545-SNJ, 9545-SNK, 9545-SPJ, 9545-SPK, 9545-TC1, 9545-TC2, 9545-TF4, 9545-TF5, 9545-TF6, 9545-TF7

The 750 and 755 lines represent IBM's flagship multimedia notebooks of the mid-90s, featuring advanced audio and video.

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.

2. 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.

ThinkPad Common Parts List

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.
2. Remove the failing devices from the replicator.
3. Unplug the AC adapter from the replicator, if attached.
4. Remove the port replicator from the computer.
5. Reconnect the failing device directly to the computer.  (If another device occupies the connector, remove it first.)
6. Go to General Checkout and follow that procedure.
7. If the advanced diagnostic device test does not find an error,  suspect a problem with the port replicator  or the system expansion bus.
8. Power-off the computer and reconnect the port replicator.
9. 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 stops in 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.

2. 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.

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

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.

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.

• 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.

2. 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.

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.

• 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.

2. 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 Adapter does 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').

2. 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.
2. Open the keyboard, and remove the battery pack and the diskette drive.
3. Remove the standby battery.
4. 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.
5. Plug the AC Adapter into the computer and power-on the computer.
6. Measure the output voltage at the connector on the system board.

   

   Pin	Voltage (Vdc)
   +	+4.0
   -	Ground

   • 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.
7. Ensure that the AC Adapter is plugged into the computer, then power-on the computer.
8. Charging of the standby battery starts. A depleted battery needs approximately 30 minutes to be recharged to the operational voltage of + 3.5 Vdc.
9. Unplug the AC Adapter.
10. 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.

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.
2. Select Test and press Enter.
3. Select a device and press Enter to run the test.
4. The test progress screen appears.
5. OK appears when the test ends without any errors.
6. Start the Advanced Diagnostic test by pressing Ctrl+A on the basic diagnostic menu screen.
7. Select Tool to install the tools.
8. 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.
9. Select OK and press Enter if the selection is OK.
10. Select a device and press Enter to start the tests.
11. Select Test All to test all devices.
12. 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.
13. 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.

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

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.

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'

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

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.

• 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.

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

please READ - 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.

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.

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

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.

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

please READ - 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.

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.

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.

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.

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

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 .
3. Raise the rear portion of the plate 3 and remove it.

   

   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.

   

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.

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.

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.

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

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

2. 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

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

   NOTE: Not all models have jacks 3 and 4.

5. Power Jack
6. Serial Connector
7. Parallel Connector
8. External Display Connector
9. Reset Pushbutton
10. 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

Common Parts Listing

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

External Diskette Drives

CD-ROM Drives

SCSI Adapters, Terminators, Cables

Rewritable Optical Drives

External Keyboard/Mouse

Enhanced Keyboards (101/102 Key)

Optional Enhanced Keyboards (101/102 Key)

Keybutton Kits (101/102 Key)

Japanese Keyboard Type 2 (106 Key, DBCS Support)

Space-Saving Keyboards (84/85 Key)

Tools and Miscellaneous

Miscellaneous Parts.

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

Model Unique Options

Models 355x, 360x, 370C

Model 370C

Model 750x

Model 755C, 755Cs

Numeric Keypad

Accessories

Tools

Power Cords

Use the power cord certified for your country.

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).

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.