Keyboard Connector Voltages - IBM 3746-900 Installation And Maintenance Manual

Keyboard
|
|
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Printer
Note: If the keyboard operation mode BIOS parameter is set to disabled, to
remove the keyboard or mouse as recommended can generate POST
errors 301 and 8603 on the 6578.
001
– Power OFF the computer.
– Disconnect the keyboard cable from the system unit.
– Power ON the computer and check the keyboard cable connector on the system
unit for the voltages shown.
All voltages are ± 5%.
Pin
1
2
3
4
5
6
Figure 3-1. Keyboard Connector Voltages
Are the voltages correct?
Yes No
002
Replace the system board.
003
On keyboards with a detachable cable, replace the cable. If the problem remains
or if the cable is permanently attached to the keyboard, replace the keyboard. If
the problem remains, replace the system board.
1. Make sure the printer is properly connected and powered on.
2. Run the printer self-test.
If the printer self-test does not run correctly, the problem is in the printer. Refer to
the printer service manual.
If the printer self-test runs correctly, install a wrap plug in the parallel port and run
the diagnostic tests to determine which FRU failed.
If the diagnostic test (with the wrap plug installed) does not detect a failure, replace
the printer cable. If that does not correct the problem, replace the system board or
adapter connected to the printer cable.
Voltage (Vdc)
+ 5 . 0
Not Used
6
Ground
4
+ 5 . 0
+ 5 . 0
2
Not Used
Chapter 3. Service Processor Troubleshooting
5
3
1
3-19