Digital Equipment DEC 3000 600 AXP, Service Information

Page: 137 / 461

Troubleshooting Tables
Using the
Tables Each troubleshooting table contains symptoms, possible causes,
and suggested actions. If more than one action is suggested,
perform them in the order listed.
System
Problems
Table 5–17 lists the symptoms, possible causes, and suggested
actions you can take to troubleshoot system problems.
Table 5–17 System Problems
Symptom Possible Cause Corrective Action
DC OK LED is off. Defective power supply. Replace the power supply.
No LEDs are on. Possible bad I/O module
and cable or system
module. Reseat the I/O module. If the
problem persists, then replace
the I/O module and then the
system module. See Chapter 3
for location and procedure.
Power-on display does
not appear and the LEDs
indicate F0. SROM jumper setting
incorrect. See Chapter 2 for setting and
location.
Power-on display does
not display and the
LEDs display DD. Monitor is not turned on. Turn on the monitor.
No screen display. Brightness and contrast
controls adjusted
incorrectly. Adjust the monitor brightness
and contrast controls.
Loose or broken cable. Verify the monitor cable/video
connections are secure.
Monitor fuse is blown. See the monitor guide for fuse
replacement instructions.
(continued on next page)
5–16