Nortel North American DMS-100 Instruction Manual page 165

1-150 Trouble locating and clearing procedures (continued)
Replacing a cooling unit electronic module
CPC A0383326, A0383327, A0383984
At the front of the cabinet
8
9
297-8021-544 Standard 14.02 May 2001
CAUTION
Possible loss of service
Disconnect power to the cooling unit before you throw the
circuit breakers. If you throw the wrong breakers, you can
disconnect power to a critical hardware component and cause
loss of service.
Throw the circuit breakers for the cooling unit.
Note: When you throw the circuit breakers, you remove power from the
cooling unit. Removal of power from the cooling unit can cause the fan
failure lamp to turn ON. The fan failure lamp is at the top of the cabinet
between the doors.
Open the cabinet doors.
To remove the cooling unit cover at the bottom of the cabinet, remove the nine
mounting screws from the cover.
Note: Do not remove the four bolts that fasten the cooling unit to the
cabinet. The procedure Replacing a cooling unit assembly in this
document shows the location of the screws.
(continued)
Cooling unit
cover
Screw
(nine)