(a)  To get access to dimmers in the P9 aisle control stand, the CDU's must be removed.

 (2)  
Four dimmers are installed behind the P7 panel.

 (a) Open the P7 panel to get access to the dimmer.
 TASK 33-11-05-004-001
 2.  Dimmer Removal from the P7 Panel
________________________________
 A.  References
 (1)  
24-22-00/201, Manual Control

 (2)  
IPC 33-11-04 Fig 5

 (3)  
SSM 33-11-02

 B.  Access
 (1)  Location Zone 200 Pilots Instrument Panel, Flight Compartment
 C.  Removal Procedure
 S 864-065
 (1)  Prepare for a dimmer removal from the P7 panel:
 WARNING: REMOVE ELECTRICAL POWER FROM THE AIRPLANE BEFORE YOU OPEN
_______ THE P7 OVERHEAD CIRCUIT BREAKER PANEL. INJURY TO PERSONNEL OR DAMAGE TO EQUIPMENT CAN OCCUR IF ELECTRICAL POWER IS ON.
 (a)  
Remove the electrical power from the airplane (Ref 24-22-00/201).

 (b)  
Make sure the STANDBY POWER switch and BATTERY switch on the P5 overhead panel are in the OFF position.

 NOTE: Standby power is not applied to the P7
____ panel when these switches are in the OFF position.
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 S 014-066
 (2)  Get access to the P7 panel dimmers:
 (a)  
Open the P7 panel to get access to dimmers T38, T40, T44 and T143.

 (b)  
Identify the dimmer to be replaced.

 S 024-067
 (3)  Remove the dimmer from the P7 panel:
 (a)  
Remove the terminal cover and the fuse holder cap from the dimmer. 1) Turn the fuse holder cap counterclockwise to release it

 from the dimmer.

 (b)  
Remove the nuts from the electrical terminals on the dimmer.

 (c)  
Disconnect the wires from the dimmer electrical terminals.

 (d)  
Remove the screws that attach the dimmer to the panel.

 (e)  
Remove the dimmer from the panel.

 S 034-068
 (4)  Remove the secondary circuit breakers from the dimmer:
 (a)  
Remove the cover(s) from the dimmer circuit breaker(s).

 (b)  
Disconnect the dimmer wires from the circuit breaker(s).

 (c)  
Remove the secondary circuit breaker(s) from the dimmer.

 1)  Keep the secondary circuit breaker(s) for installation on the replacement dimmer.
 TASK 33-11-05-404-011
 3.  Dimmer Installation in the P7 Panel___________________________________
 A.  References
 (1)  
24-22-00/201, Manual Control

 (2)  
IPC 33-11-04 Fig 5

 (3)  
SSM 33-11-02

 B.  Access
 (1)  Location Zone 200 Pilots Instrument Panel, Flight Compartment
 C.  Installation Procedure
 S 034-069
 (1)  Install the secondary circuit breakers on the dimmer:
 (a)  
Connect the dimmer output wires to the secondary circuit breaker(s).

 (b)  
Install the secondary circuit breaker(s) on the dimmer.

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 (c)  Install the cover(s) on the dimmer circuit breaker(s).
 S 424-070
 (2)  Install the dimmer in the P7 panel:
 (a)  
Put the dimmer in its position in the panel.

 (b)  
Install the screws that attach the dimmer to the panel.

 (c)  
Connect the electrical wires to the dimmer terminals.

 CAUTION: TIGHTEN THE NUTS ON THE DIMMER ELECTRICAL TERMINALS TO 12
_______ TO 15 LB-IN (1.4 TO 1.7 KM). OVERTIGHTENING MAY RESULT IN STUD BREAKAGE ON THE DIMMER MODULE.
　
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