Fault Isolation Tests; Faulty Line Drawer; Faulty Shelf Circuit Pack; Faulty Line Card - Nortel DMS-100 Series Maintenance Manual

Fault isolation tests

When the system detects a fault condition in the OPM, maintenance action is
required. Fault isolation tests determine which component causes the fault.
Fault isolation tests determine if the fault condition requires immediate
correction or if the fault condition must be reported to the correct maintenance
support organization. The following sections list the procedures involved in
how to isolate and correct faults with specified OPM components.

Faulty line drawer

To handle a defective line drawer:
1 Post, busy, test, and RTS the drawer.
2 If a test or RTS fails with a card list, replace the cards with a correct card
replacement procedure. Test and RTS the drawer.
3 If a test or RTS fails without a card list, perform the correct tests that the MAP
response indicates. RTS the drawer.

Faulty shelf circuit pack

To handle a defective shelf circuit pack:
1 Post the line concentrating module (LCM).
2 Determine if any fault indicators are present.
3 Busy the unit that has the defective card.
4 Perform the correct card replacement procedures.
5 Test and RTS the LCM unit.

Faulty line card

If a single card fails during line card diagnostics, the card causes a whole LCM
unit to fail. Location of the single defective card can be difficult. Normally
this condition affects only one unit of the LCM. The following two procedures
can identify the defective card.
Perform procedure 1 during a maintenance window to avoid any service
interruptions. Qualified technicians can perform this procedure during the day
if the technicians take correct precautions.
To identify a defective card:
Procedure 10-1
1 Find the vertical connection to the LCM in trouble. Use Table MTAVERT.
2 Use a buttset with caution on the backplane of the MTADRIVER.
Trouble isolation and correction 10-3
DMS-100 Family OPM Maintenance Manual XPM14 and up