Nortel DMS-10 Series Installation, Operation And Maintenance Manual page 451

Status and Alarm Lamp Replacement
Procedure 6-1
Status and Alarm Panel lamp test and replacement
Step Description
CAUTION
It is recommended that Status and Alarm lamp replacement be performed
by qualified maintenance personnel.
7
Remove the front panel of the BMC, A chassis. Refer to Figure 6-5.
8
Note which lamps are already lit. The lamps reflect current BMC operating mode.
9
Press the spring-loaded switch to the LT position. If a lamp fails to light, proceed to step
3, else procedure complete; go to step 7. All lamps light; the lamp(s) indicating the current
status of the BMC stay lit when the switch is released.
Loosen the four captive screws located on the left and right hand sides of the
front panel; carefully remove the front panel. Once removed, put the front panel in a safe
place to avoid damage; bending and scratching.
10
Remove the defective lamp by wedging a screwdriver blade between the lamp body and
the edge of the panel cut out. Use a back and forth motion until it releases from the
socket. Place a finger on the side of the lamp opposite the blade and rock the lamp gently.
11
Insert the new lamp. Make sure that the leads of the new lamp do not bend during
insertion.
12
Press the LT rocker switch. Verify operation of the replacement lamp.
13
Put the front panel back on the A chassis.
Error Control II PCA Jumper LED
The LED on the Error Control II Jumper PCA (slot B5) lights to indicate the
toggle switch on the PCA has been activated (up position). This toggle
switch is activated during replacement of the Error Control II PCA (slot A5).
This LED is not cannot be replaced in the field.
TEC/DSI Alarm
The TEC/DSI Alarm is activated when the TEC/DSI PCA fails its own self-
diagnostic check. At this point, the TEC/DSI PCA sends an alarm bit (EOT)
BMC II BISYNC Operation, Administration, and Maintenance Guide BMCB001 and up
Section 060-INDP-610 Maintenance Procedures Guide 6-13