Locating And Clearing Faults - Nortel DMS 100 Series Maintenance Manual

Table 8-1 Assessing PM alarms from the MAP display (Sheet 2 of 2)
MTC level
PM RCO2
*C*
PM RCO2
*C*
Use the following guidelines when you respond to alarms:
•
•
•
For instructions on how to clear an alarm, refer to the Alarm Clearing
Procedures in this document.

Locating and clearing faults

This section contains standard fault detection steps to locate and clear faults:
1. Silence audible alarms that the system generates when the system detects
2. To isolate the fault, read status displays and trace fault codes to the menu
DMS-100 Family Remote Switching Center Multi-Access Maintenance Manual XPM11 and up
PM level
SysB 1
SysB 1
More than one alarm of the same severity can appear on the MAP display.
When this event occurs, clear the alarms from the left of the screen to the
right.
If a more severe alarm occurs when you fix an alarm, respond to the new
alarm.
Standard pulse coded modulation (PCM30) link alarms and cyclic
redundancy checking (CRC-4) failures indicate failed and out-of-service
(OOS) link equipment.
alarm conditions.
level required to clear the fault.
RSC-M trouble isolation and correction 8-3
Possible scenarios
Both units are SysB. If the cause of this state is
communication with the host, the RSC-M enters
emergency stand-alone (ESA). The following
sequence of logs generates when the RSC-M
enters ESA:
• PM109—The carrier is busy.
• PM128—The RSC-M is in-service trouble
(ISTb).
• PM107—The RSC-M is central-side (C-side)
busy (CBsy).
• PM107—The line concentrating modules (LCM)
are CBsy.
• PM102—The RSC-M is SysB.
• PM181—The RSC-M attempts to restart the
message links.
Both PPs are defective, so both units are SysB.
Both RSC-M units are OOS. Both voice and data
services are lost.