Lenovo 8085 Computer Accessories User Manual


 
Message/Symptom FRU/Action
Some or all keys on the keyboard do not
work
1. Keyboard
2. Keyboard Cable
3. System Board
Undetermined problems
Check the power supply voltages (see “Power Supply Errors” on page 59). If the
voltages are correct, return here and continue with the following steps.
1. Power-off the computer.
2. Remove or disconnect the following components (if installed) one at a time.
a. External devices (modem, printer, or mouse)
b. Any adapters
c. Riser card
d. Memory modules
e. Extended video memory
f. External Cache
g. External Cache RAM
h. Hard disk drive
i. Diskette drive
3. Power-on the computer to re-test the system.
4. Repeat steps 1 through 3 until you find the failing device or adapter.
If
all devices and adapters have been removed, and the problem continues, replace
the system board.
90 Hardware Maintenance Manual