IBM pSeries 690 Service Manual page 905

Method 1. Testing MCMs and Pass Through Modules for a Short Circuit
Performing this test ensures that a short circuit was not created when installing an MCM or a pass through
module. Follow the procedure to install and use the MCM/L3 module short-circuit test tool (part number
44P0209) and a multimeter during MCM replacement.
Note: This procedure is to be performed by trained personnel only. Ensure the UEPO switch is in the Off
position before performing these procedures.
MCM Installation Shorts Test, Step 1:
Attention: Be sure to record the resistance readings taken during these tests so that you can refer to
them if needed.
Install first MCM module
[U1.18-P1-Cx] (a load is required
before the meter is connected)
* See "Shorts Test Qualified Service Meters and Fail Criteria" on page 916.
Power Down The System
Disengage All DCAs from Planar
Install Test Card in DCA Location 6 [U1.18-P1-V8]
No Meter Attached
Wait 1 Minute to allow any charge to dissipate
Select Meter to be used for this test *
Only Meters recorded in the Qualified Meters table are to be used *
The most accurate meter available is to be used
Record The Meter Model Used and the Fail Criteria for the model *
(the Fail Criteria is in the right column of the qualified meters table)
Calibrate Meter
Do not attach meter to test card at this time
Set meter to the range defined in the table *
Power Meter Off & On
Short The Meter Leads Together
Record Meter Reading. Call this resistance "Meter Lead Resistance" (MLR)
NO
Are MCMs In
the System
Connect Meter
Meter "V" to Test Card "1.6V (Yellow Jack)
Meter "COM" to Test Card "COMMON RET" (Black Jack)
EPO Off
Yes
A
Chapter 9. Removal and Replacement Procedures
889