Monitoring
6-10 9820-A2-GB20-20
June 2000
Power Module LEDs (Model 9820-45M)

Each power module has a green LED which remains lit while power is applied

and the power module is functioning.

When the yellow front panel System PWR LED is lit, one of the power modules

has failed. The failed power module can be identified from the back of the DSU

by its unlit LED.

Table 6-8. Power Module Troubleshooting

Configuration Symptom What to Do

(in order, if problem persists)

One Power
Module No front panel LEDs are
lit. 1. Verify that the receptacle in use
provides 120 Vac.
2. Verify that the power module switch is
in the On position.
3. Replace the power module. See
Replacing a Power Module
in
Chapter 12,
Hardware Maintenance
.
4. Call your service representative.
Two Power
Modules No front panel LEDs are
lit. 1. Verify that the receptacles in use
provide 120 Vac.
2. Verify that the power module switches
are in the On position.
3. Replace the power modules. See
Replacing a Power Module
in
Chapter 12,
Hardware Maintenance
.
4. Call your service representative.
The front panel System
PWR LED is lit. 1. Check the power module LEDs from the
back of the unit and replace the failed
power module (the one whose LED is
off). See
Replacing a Power Module
in
Chapter 12,
Hardware Maintenance
.
2. Call your service representative.