Lenovo 20X1 Hardware Maintenance Manual page 45

b. Devices attached to the docking station or the port replicator
c. Printer, mouse, and other external devices
d. Battery pack
e. Hard disk drive or solid-state drive
f. External diskette drive or optical drive
g. Memory module
h. PC cards
4. Turn on the computer.
5. Determine whether the problem has been solved.
6. If the problem does not recur, 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 nondefective FRU):
a. System board
b. LCD unit
.
Chapter 4 Related service information
39