Lenovo ThinkPad 360 Hardware Maintenance Manual - Page 429

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 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" on page 398.) 1. Power-off the computer. 2. 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. 3. Remove or disconnect all of the following devices. a. Non-IBM devices b. Devices attached to the expansion bus connector c. Printer, mouse, and other external devices d. Battery pack e. Hard disk drive f. Diskette drive or the device attached to the diskette drive connector g. IC DRAM card or DIMM card h. PC Cards 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. 4. Power-on the computer. 5. Determine if the problem has changed. 6. If the problem does not occur again, reconnect the removed devices one at a time until you find the failing FRU. 7. If the problem remains, replace the following FRUs one at a time. Do not replace a non-defective FRU. DC/DC card Interposer card LCD assembly System board Processor card ThinkPad 755CE, 755CSE, 755CV, 755CX (9545) 419