IBM RS/6000 SP, Maintenance Information

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MAP 0340: POWER3 SMP Thin and Wide Node Power
041
– Check circuit breaker(s) at front of power supplies. Put these circuit breaker(s) in the On (‘1’) position if
they are not already.
Do the circuit breakers go (trip) to the Off (‘0’) position?
Yes No
042
– Go to Step 050 on page 1-205.
043
– Place processor node in service position.
Attention: Some 48-volt power cables have in-line circuit breakers. Ensure the in-line circuit breaker
switch is in the Off (O) position before connecting or disconnecting 48-volt power cables from the node.
– Check the 48-volt bulk power harnesses at power supplies in the rear of the node, at the connection to
the circuit breakers, and at the 48-volt bulk power connections for any obvious problems which might
cause a short.
Does everything appear to be okay?
Yes No
044
– Fix obvious problem(s).
– Remove processor node from service position.
– Reconnect all cables at rear of the processor node.
– Go to Step 041.
045
– Using a multimeter, check for a short between the pins of the 48-volt input connector(s) (J8 at the rear
of the node).
Was a shorted condition detected?
Yes No
046
– Disconnect the 48-volt power cable(s) from the SEPBU bulkhead.
– Using a multimeter, check for a short between pins in the 48-volt power cable(s).
– Using a multimeter, check for a short between any pins in node power plug(s).
– If a short is detected, replace the 48-volt power cable.
– Using a multimeter, check for a short between any tabs in circuit breaker(s).
– If a short is detected, isolate it to either the cable or circuit breaker and replace the corresponding
part.
– Remove processor node from service position.
– Reconnect all cables at rear of the processor node.
– Go to Step 041.
047
– Using a multimeter, check for a short between the pins of the power/supervisor connector at the rear of
the front assembly.
(Step 047 continues)
1-204
RS/6000 SP MAPs