IBM RS/6000 SP, Maintenance Information

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MAP 0240: Wide Processor Node DC Short/Open
MAP 0240: Wide 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 +4 V dc, +5 V dc, +12
V dc, and/or -12 V dc to ground.
– Based on the message, use the information in the table below to disconnect the appropriate cable and
check resistance between the cable pins.
Voltage Cable
From
(positive lead) To GND
(negative lead) Acceptable Range
(in ohms)
+4 V N00-PC-P16A Pin 4 Pin 10 6 - 25
+5 VM N00-PC-P13A Pin 4 Pin 10 1K - 5M
+5 VI N00-PC-P40A
N00-PC-P45
N00-PC-P65 Pin 10
Pin 4
Pin 4 Pin 1
Pin 3
Pin 3 10 - 30
100 - 500*
100 - 500*
+12 V N00-PC-P40A
N00-PC-P45
N00-PC-P65 Pin 6
Pin 1
Pin 1 Pin 1
Pin 2
Pin 2 800 - 100K
1K - 5K*
1K - 5K*
−
12 V N00-PC-P40A Pin 3 Pin 1 1K - 20K*
Note: *Resistance range assumes DASD(s) attached on this cable. With no DASD(s) attached, an open will be
measured.
– The following table shows cable connections:
Connector Component
N00-PC-P16A
N00-PC-P13A CPU planar
N00-PC-P40A I/O planar
N00-PC-P45
N00-PC-P65 DASD 3 / DASD 4
DASD 1 / DASD 2
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 power cable.
Ÿ
Open in voltage distribution caused by a shorted component. Refer to list in Step 001 for
suspect component(s).
– Remove the suspect component(s) and inspect for damage. Also check the following list for other
suspect parts:
Ÿ
Micro Channel adapter cards
(Step 002 continues)
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RS/6000 SP MAPs