Chapter 2 PEM Faults and Fan Assembly Failures

DC PEM Faults

Table 2-2 AC PEM Fault Symptoms and Corrective Action (continued)

PEM experiences

1. Ensure that the input power to both slots is correct.

problems in one

2.

Verify that no connections have been made to the DC-power connectors

slot but operates

 

underneath each PEM.

normally in a

 

3.

If the problem persists, contact Cisco TAC.

different slot

 

 

Fault LED is lit

1. Verify that no connections have been made to the DC-power connectors

yellow

 

underneath each PEM.

 

2.

Verify that the PEM is fully inserted into the power bay and that its captive

 

 

screws have been tightened.

 

3.

Check to see if the power switch is set to the standby position. If so, set the

 

 

switch to the ON position.

 

4.

If the problem persists, flip the power switch on the PEM to the standby

 

 

position, wait several seconds, and then back to the ON position.

 

5.

Replace PEM with a known good replacement.

 

6.

Contact Cisco TAC.

 

 

 

Tip Securely tighten the captive screws on your PEMs to prevent heightened levels of electromagnetic interference.

DC PEM Faults

On the Cisco uBR10012 router, two DC PEMs are in a redundant configuration, which allows one DC PEM to fail without affecting system operations. A single PEM can usually power the router for sufficient time to request and install a new PEM to replace the one that failed.

Tip To quickly check the functional status of your PEMs, use the show environment command.

DC PEM faults can occur for the following reasons:

PEM failure

Reversed power cables

Backplane interface failures or damage Two models of the DC PEM exist.

Figure 2-2shows the front panel of the original DC PEM (UBR10-PWR-DC) that was initially produced for the Cisco uBR10012 router.

Figure 2-3shows the front panel of the DC PEM that is currently being produced for the

Cisco uBR10012 router. The new model of the DC PEM (UBR10-PWR-DC-M) is identical in form and function to the first version, except that it includes a connector on the front panel for connecting to the alarm status connectors on the optional 2400-watt AC-input power shelf.

Table 2-3describes the indicators on the front panel of both models of DC PEM.

Cisco uBR10012 Universal Broadband Router Troubleshooting Guide

 

OL-1237-01

2-3

 

 

 

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Cisco Systems UBR10012 manual DC PEM Faults