HP 3562A Service Manual page 408

MODEL 3562A
Use paragraph 7-14 for the location of the service test keys.
To turn the loop mode on press the following keys:
SPC L
. . . . . . SERVIC
FCTN
Press the keys to start a self-test. Failures of a test are entered in the test log, the self-test
stops, and the test log is displayed.
To turn the loop mode off press A2 S1 (reset switch on A2 CPU) or press the keys as follows:
. .
RET U R N
Troubleshooting Hints
1 . Common causes of intermi t tent failures are:
Cold solder joints
Loose cables
ICs loose in sockets
Loose screws on power supply
An assembly partially out of its card nest
2. An intermittent failure in the instrument can be caused by an assembly's bottom
connector that attaches the assembly to the A 12 Mother Board. Check for loose
pins on the connector.
If the instrument intermittently fails to power up, the most likely cause is the power
3.
supply control circuits (go to 8-16).
4. Intermittent keyboard failures can be caused by the ribbon cable (W10) between
the A1 5 Keyboard and A12 Mother Board.
7-44
TEST
. . . . . . LOOP
ON
. LOOP
. . .
OFF
FAULT ISOLATION