IBM RS/6000 SP, Maintenance Information

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MAP 0180: Thin Processor Node DC Short/Open
MAP 0180: Thin Processor Node dc Short/Open
Note: Refer to "Service Position Procedures" in IBM RS/6000 SP: Maintenance Information, Volume 3,
Locations and Service Procedures for placing or removing processor node(s) in/from service posi-
tion.
001
Problem in processor node power distribution detected by checking resistances of +5 V dc, +12 V dc,
and/or
−
12 V dc to ground. The following table refers to I/O Planar jack N00-PL-J2:
Voltage
Measure From
(positive lead) To GND
(negative lead)
Acceptable Range
+5 V dc Pin 1 (red) Pin 2 (black) 5 - 30 Ohms
+12 V dc Pin 3 (yellow) Pin 2 (black) 100 - 5000 Ohms
−
12 V dc Pin 9 (purple) Pin 2 (black) 500 - 900 Ohms
Was resistance below acceptable range?
Yes No
002
Measured resistance is too high.
– Check for one or more of the following conditions:
Ÿ
Open in planar power cable from node supervisor card N00-NS-J102 to I/O planar N00-PL-J2.
Ÿ
Open voltage plane in I/O planar caused by a shorted component.
– Remove all adaptor cards, memory cards, fixed disk drives, and the CPU card from the I/O
planar. Inspect components for damage.
– Remove I/O planar and inspect for damage.
– Replace any damaged components found during inspection.
– Continue at Step 009 on page 1-85.
003
Measured resistance is too low.
Are there any Micro Channel slots empty?
Yes No
004
Micro Channel power specifications may be exceeded by card requirements.
Has customer recently added or exchanged Micro Channel adaptors?
Yes No
005
– Go to Step 009 on page 1-85.
006
– Remove processor node from service position.
– Reconnect all cables at rear of the processor node.
– Remove the most recent adaptor(s) from this processor node.
(Step 006 continues)
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RS/6000 SP MAPs