Undetermined Problems - Lenovo ThinkPad Hardware Maintenance Manual

1. Run the 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.

Undetermined problems

If the diagnostic tests did not identify the device that has failed, if wrong devices are installed, or if the
system simply is not operating, follow these procedures to isolate the failing FRU.
1. Verify that all attached devices are supported by the tablet.
2. Verify that the power supply being used at the time of the failure is operating correctly. See "Power
system checkout" on page 26.
3. Turn off the tablet.
4. Visually check each FRU for damage. Replace any damaged FRU.
5. Disconnect all external devices, such as the printer, mouse, and optical drive.
6. Remove the following devices:
a. Non-ThinkPad devices
b. Battery pack
c. Main storage drive
d. Memory module
e. PC cards
7. Connect the ac power adapter and turn on the tablet.
8. Determine whether the problem has been solved.
9. If the problem does not recur, reconnect the removed devices one at a time until you find the failing FRU.
10. If the problem remains, replace the following FRUs one at a time (do not replace a nondefective FRU):
a. System board
b. LCD assembly
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Hardware Maintenance Manual