Nortel North American DMS-100 Instruction Manual page 247

1-232 Trouble locating and clearing procedures (continued)
Replacing an NT9X95 card in a cooling unit
At the front of the cabinet
8
9
At the back of the cabinet
10
11
297-8021-544 Standard 14.02 May 2001
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 causes 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 these screws.
Remove the two screws that fasten the electronic module to the cooling unit
assembly.
Note: The screws are near the upper left-hand corner of the back plate of
the cooling unit.
Disconnect the power connector from the electronic module.
Note: The power connector is near the upper left-hand corner of the back
plate of the cooling unit.
(continued)
Cooling unit
cover
Screw
(nine)