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CiscoASR 9000 Series Aggregation Services Router Hardware Installation Guide
Chapter4 Troubleshooting the Installation
Troubleshooting the Power Subsystem
Troubleshooting the Power Distribution System
The power distribution system consists of:
•AC or DC power modules, which supply –54VDC to the backplane.
•Chassis backplane, which carries voltage to chassis components.
•DC-to-DC converters, which convert –54VDC from the backplane to the correct voltages required
by the line cards.
Follow these steps to troubleshoot the power distribution system:
Step1 Check each power module to make sure that:
•Power module door is fully closed and properly secured by its latch.
•Green Input Power LED is on.
•Green Output Power LED is on.
•Red Fault LED is off.
If the power modules meet the above criteria, then the correct source power is present and within
tolerance and output DC power is present. The power modules are functioning properly.
Step2 Make sure the fan trays are operating:
•If the fan trays are functioning, then the –54VDC from the chassis backplane and the cables from
the backplane to the fan trays are functioning properly.
•If one or both fan trays are not functioning, there may be a problem with either the fan trays
themselves, or the –54 VDC power supplied to the fan trays. Eject and reseat the fan trays.
•If a fan tray is still not operating, there could be a problem with the fan tray controller card or cable.
Replace the fan tray.
•Contact your Cisco representative if replacing a fan tray or both fan trays does not fix the problem.