DEC 4000 600 series, Owner'S Manual, Page: 201 / 242

Power Problems
Power Problems
Power
Problems This section describes how to troubleshoot the system when
there is no power at the system enclosure or the power supply
subsystem lights indicate power trouble.
Table 9–4 describes possible power problems and their solutions.
The next section, Power Supply Lights, explains how to interpret
the lights.
Table 9–4 Diagnostic Flow for Power Problems
Symptom Action Reference
No AC power at system. AC
present light is off. Check the power source and power cord.
AC power is present, but
system does not power on. Check the AC circuit breaker setting.
Check the DC on/off switch setting.
Examine power supply subsystem lights to
determine if a power supply unit or fan has
failed, or if the system has shut down due to an
overtemperature condition. Figure 9–1,
Table 9–5
Power Supply
Lights The power supply lights on the rear of the system (Figure 9–1)
are used to indicate the status of the components that make up
the power supply subsystem. Refer to Table 9–5 for information
on interpreting the lights and determining what actions to take
when a failure is indicated.
Troubleshooting the System 9–5