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

5 Return the hardware to service.

Fault isolation tests

The detection of a fault condition in the RCLM requires a maintenance
action. Fault isolation tests determine the location of the fault. The tests
correct the fault condition. These test results must be reported to the
appropriate maintenance support. The following sections list the procedures
to isolate and correct faults with specified RCLM components.

Defective line drawer

To handle a defective line drawer:
1 Post, busy, test, and RTS the drawer.
2 If test or RTS failure occurs with a card list, use an appropriate card
replacement procedure to replace the cards. Test the cards again and
RTS the drawer.
3 If test or RTS failure occurs without a card list, perform the MAP
terminal response tests and RTS the drawer.

Defective shelf circuit pack

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

Defective line card

If one card failure occurs during the line card diagnostics test, the failure
causes failure of the whole LCM unit. The defective card can be difficult to
locate. Two procedures are available which maintenance personnel can use
to locate the defective card.
Perform procedure 1 during a maintenance window to avoid possible service
interruptions. Technicians with experience can perform this procedure
during busy service periods.
Procedure 1
To identify a defective card:
1 Find the vertical connection to the LCM in trouble. Use Table
MTAVERT.
2 Carefully use a buttset on the backplane of the MTADRIVER.
DMS-100 Family RLCM Maintenance Manual XPM12 and up
Trouble isolation and correction 10-3