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Cisco Wide Area Application Engine 7326 Hardware Installation Guide
OL-6831-02
Chapter5 Troubleshooting the System Hardware
Checking the Power Subsystem
Note If diagnostic error messages appear that are not listed in the tables, make sure that
your device has the latest levels of BIOS and diagnostics microcode installed.
Checking the Power Subsystem
Power problems can be difficult to solve. For example, a short circuit can exist
anywhere on any of the power distribution buses. Usually a short circuit will cause
the power subsystem to shut down because of an overcurrent condition.
To perform a general procedure for troubleshooting power problems, follow these
steps:
Step1 Power down the device and disconnect all AC power cords.
Step2 Check for loose cables in the power subsystem. Also check for short circuits, for
example, if there is a loose screw causing a short circuit on a circuit board.
Step3 Remove adapters and disconnect the cables and power connectors to all internal
and external devices until the device is at the minimum configuration required to
start it.
Step4 Reconnect all AC power cords and power up the device. If the device starts up
successfully, replace adapters and devices one at a time until the problem is
isolated. If the device does not start up from the minimal configuration, replace
components of a minimal configuration one at a time until the problem is isolated.
To use this method, it is important to know the minimum configuration required
for a system to start.