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1-20
Troubleshooting During Power-Up
Figure 1-16 XMI PIU Troubleshooting Steps - MOD OK LED Off
Front
BXB-0084-92
MOD OK
OC
OT
OV
48V
RESET
V-OUT
DISABLE
MOD OK
OC
OT
OV
48V
Both
MOD OK
LEDs Off
Check that the V-OUT/DISABLE switch is in the
V-OUT (up) position.
Is the clock card inserted in slot 7 of the I/O card cage?
.
Check the CCL-to-PIU cabling.
Replace that power regulator.
Only One
MOD OK
LED Off
Check the internal bias at power regulator B .
Yes
Yes
B
A
If low, unplug regulator A and retest the bias.
Bias normal at regulator B? Replace regulator A.
Bias still low at regulator B? Replace regulator B.
Check the PIU LEDs on the CCL module (see
Section 1-5).