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Chapter 4 Troubleshooting the Installation
Troubleshooting a DC Power Subsystem
Step 4 Power off the PEM circuit breaker switch and check the DC power source.
•Check the DC power wires from the power source to the router.
–Verify that the power wires are fastened securely at the PDU and the DC source.
–Verify that the power wires are not worn or damaged. If the insulation appears cracked or broken, have the power wires replaced.
•Make sure that the DC power source circuit breaker is on, and that it has the proper current rating.
•Verify that each PEM in the router is attached to a separate DC power source.
•Power on the PEM circuit breaker.
–If the PEM INPUT OK LED goes on, go to Step 6.
–If the PEM INPUT OK LED remains, go to Step 5.
Step 5 Remove the PEM and insert it in the second bay in the router, or into a bay on another Cisco XR 12406 router.
•If the INPUT OK LED remains off, the PEM is faulty and needs to be replaced.
•If the INPUT OK LED goes on, the input portion of the PEM is working normally, go to Step 6.
Step 6 Is the OUTPUT OK LED on?
•If yes, the power source is good and the PEM is operating normally.
•If no, and there is no other system activity (blower module is off; line cards are unpowered), the PEM is fault. Replace the PEM.
•If no, but the blower module is operating, it means all internal DC voltages are within tolerance. Suspect a faulty OUTPUT OK LED.
–Use the show environment command to check the voltages on each card. The blower module uses
Note In a Cisco XR 12406 router with two power supplies, the output power from the second power supply is adequate to maintain router operation.
| Cisco XR 12406 Router Installation Guide |
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