Nortel Meridian 1 Manual page 155

Possible cause
Defective PE shelf
Action
Unseat the affected trunk card and enable the TN.
If you do not receive an OVD message, test superloop TNs by entering:
LD 30
UNTT l s c u
Test TNs on other loops by entering:
LD 45
TEST
If you receive an OVD message, replace the card cage assembly in the
module.
Clearing trunk faults
Meridian 1 Fault clearing
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