IBM RS/6000 SP, Maintenance Information

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MAP 0410: Supervisor Power 24 Volts DC Problem
005 (continued)
– Using a multimeter, measure resistance from contactor coil pin A1 (positive lead) and A2 (negative
lead).
Is resistance
<
40 ohms?
Yes No
006
– For RS/6000 SP frames, r24 V supervisor power supply.
– Replace supervisor power supply.
– Reconnect ac and put main circuit breaker in the On (‘1’) position.
Does the Power Distribution Unit rear panel LED light?
Yes No
007
– Check for a cable problem. Replace power distribution unit if necessary.
– Go to “MAP 0570: End of Call” on page 1-357.
008
Supervisor power 24 V dc is now present in system.
Is the problem resolved?
Yes No
009
Problem not resolved.
– Go to “MAP 0370: Main Power” on page 1-222.
010
Problem resolved.
– Go to “MAP 0570: End of Call” on page 1-357.
011
– Disconnect wire from contactor coil pin A1 or A2, then measure resistance between contactor pin A1
and A2.
Is resistance
<
40 ohms?
Yes No
012
– Go to Step 002 on page 1-244.
013
– Replace contactor.
– Reinstall cover over Power Distribution Unit ac section.
– Reconnect ac power, then with the main circuit breaker in the On (‘1’) position, check Power Distribution
Unit rear panel LED.
(Step 013 continues)
Chapter 1. Maintenance Analysis Procedures (MAPs)
1-245