IBM H Series Installation And Service Manual page 59

Step 1520-6
Note: Either the Fan monitor control card or the power distribution board may be
defective.
To test each FRU, exchange the FRUs that have not already been exchanged in the
following order.
Fan monitor control card
Power distribution board
1. Turn the power off.
2. Unplug the power cable from the power supplies.
3. Exchange one of the FRUs in the list.
4. Connect the power cables to the power supplies.
5. Turn the power on.
Does the fan in the power supply turn on and the power LED on the operator
panel come on and stay on?
NO Reinstall the original FRU.
Repeat this step until the defective FRU is identified or all the FRUs have
been exchanged.
If the symptom did not change and all the FRUs have been exchanged,
Go to "Step 1520-7" on page 2-26.
YES Go to "MAP 410: Repair Checkout" in the Diagnostic Information for Mul-
tiple Bus Systems.
Chapter 2. Maintenance Analysis Procedures
2-25