Locating And Clearing Faults - Nortel DMS-100 Series Maintenance Manual

10-2 Trouble isolation and correction
Alarms
Audible and visual alarms indicate that maintenance is required. Correct
performance of routine system maintenance and use of OMs and logs
minimizes the occurrence of alarms.
The level of the alarm indicates how severe the alarm is and the degree of
maintenance required. The alarm levels are minor, major or critical. The
following table describes alarm conditions.
Alarm description
Alarm
Minor
Major
Critical
The following guidelines are followed for alarm response:
For alarm clearing procedures, refer to the Alarm Clearing Procedures.

Locating and clearing faults

The standard troubleshooting steps for how to locate and clear faults are as
follows:
1 Silence any audible alarms the system causes after detection of alarm
2 To isolate the fault, read the status displays and trace fault codes to the
3 Busy the hardware to remove system access to the defective component.
4 Test the defective component and identify the cards that you must
297–8351–550 Standard 04.01 August 1999
MAP display
(blank)
(M)
(*C*)
When several alarms of the same severe condition appear on the MAP
display screen, clear the alarms on the screen from left to right.
If, when you correct an alarm, an alarm that is more severe occurs,
respond to the new alarm. Do not continue attempts to clear the previous
alarm.
conditions.
menu level needed to clear the fault.
The removal of access prevents system interference and allows the
performance of maintenance activity.
replace. Replace the defective card and test it again.
Description
Normally does not affect service.
Normally indicates a condition that degrades
service.
Normally indicates a service power failure or
possible service power failure.