Northern Telecom DMS-100 Series Maintenance Manual page 217

Procedure 7-1
Testing and Replacing the Status and Alarm Lamp
Step Description
1 Remove the front panel of the DPP,
A chassis.
2 Note which lamps are already lit.
3 Press the spring-loaded switch to the LT
position. If a lamp doesn't light, go to step
4; else procedure is complete; go to step 7.
4 Loosen the four captive screws on the left
and right sides of the front panel; carefully
remove the front panel.
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.
5 Insert the new lamp.
6 Press the Lamp Test rocker switch.
7 Replace the front panel on the A chassis.
CAUTION
Only qualified maintenance personnel should replace
the Status and Alarm lamp.
End
DPP Recovery and Routine Maintenance Guide BCS35 and up
Routine maintenance 7-3
Notes
See Figure 7-2.
The lamps reflect current DPP operating
mode.
All lamps light; the lamp(s) showing current
DPP status stay lit when the switch is
released.
Once removed, put the front panel in a safe
place to avoid bending and scratching.
Place a finger on the side of the lamp
opposite the blade and gently rock the
lamp.
Make sure the leads of the new lamp do not
bend during insertion.
Verify operation of the replacement lamp.