IBM PS/1 User Manual

003 (continued)
DID YOU RECEIVE A 3XX POST ERROR?
Yes No
004
Go to Step 008 on page 2-56.
005
(From steps 008, 010, and 013)
– Power off the system unit and wait 10 seconds.
– Disconnect the keyboard cable from the system unit.
– Power on the system unit.
– Check the voltage at the keyboard cable connector on the system board,
shown in Figure 2-5, after the POST.
Note: Measure voltages with respect to Ground (Pin 3).
Pin
1
2
3
4
5
6
Voltage (Vdc)
+5.0
Not Used
Ground
+5.0
Clock
Not Used
1
6
2
3
4
5
Figure 2-5. Keyboard Connector Voltage Check
ARE THE VOLTAGES CORRECT?
Yes No
006
Replace the system board.
007
Replace the keyboard. If the symptom remains, replace the system board.
Diagnostic Information 2-55

IBM PS/1 Specifications

General

Processor	Intel 80286 or 80386
Processor Speed	10 MHz (80286)
RAM	1 MB (expandable to 2 MB or more)
Storage	40 MB hard drive
Floppy Drive	3.5" 1.44 MB
Graphics	VGA
Ports	Serial, Parallel, Mouse