S 862-015
 CAUTION: REMOVE THE EXTERNAL POWER, ENGINE GENERATOR POWER, APU
_______ GENERATOR POWER, AND ALL BATTERY POWER FROM THE AIRPLANE BEFORE YOU DO REPAIRS TO THE WIRES. WHEN YOU DO THE REPAIRS, THE WIRE WRAP POSTS DO NOT HAVE COVERS INSTALLED. SPARKS BETWEEN THE WIRE WRAP POSTS CAN CAUSE DAMAGE TO THE EQUIPMENT.
 (1)  Remove all the electrical power (Ref 24-22-00/201).
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 (2)  S 862-016Remove all the battery power.
 (3)  S 012-017Remove the cargo lining from the aft side of the electronic rack: (a) Remove the bolts. (b) Remove the cargo lining.
 S 492-073

 CAUTION:_______YOU MUST PUT A ESD WRIST STRAP ON YOUR WRIST. YOU MUST CONNECT THE ESD WRIST STRAP TO THE ELECTROSTATIC GROUND RECEPTACLE ON THE WIU RACK. MAKE SURE THE ESD WRIST STRAP IS ON YOUR SKIN. IF THERE IS MATERIAL BETWEEN THE STRAP AND YOUR SKIN, THE GROUND CIRCUIT WILL NOT BE SATISFACTORY. THE ELECTRONIC SHELVES AND THE WIRES ARE CONNECTED TO ELECTROSTATIC SENSITIVE EQUIPMENT. IF YOU DO NOT CORRECTLY USE THE ESD WRIST STRAP, YOU CAN CAUSE MUCH DAMAGE TO THE EQUIPMENT.
 (4)  Attach a ESD wrist strap to your wrist.
 NOTE: The ESD wrist straps are kept in bags at the ends of the
____ WIU racks (Fig. 201).
 S 492-018
 (5)  Attach a ESD wrist strap to the electrostatic ground receptacle on the WIU rack (Fig. 201).
 S 012-075
 CAUTION: DO NOT PERMIT CONTAMINATION IN THE WIU WHEN THE COVER IS OFF.
_______ MAKE SURE THAT YOU KEEP CONTAMINATION OR UNWANTED MATERIAL AWAY FROM THE WIU. MAKE SURE THAT OTHER PEOPLE THAT WORK AROUND THE WIU AREA KEEP UNWANTED MATERIAL OR CONTAMINATION AWAY FROM THE WIU. UNWANTED MATERIAL OR CONTAMINATION CAN CAUSE A MALFUNCTION IN THE WIU.
 (6)  Remove the WIU cover from the applicable shelf:
 (a)  Remove the bolts that hold the cover (View B, Fig. 201).
 NOTE: Do not loosen the center bolt at the top of the cover.
____ The bolt at this location is in a slot and does not hold the cover.
 (b)  Remove the cover.
 S 012-020
 (7)  Remove the post cover from the wire wrap post where you will replace the wires.
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 S 022-068
 CAUTION: REMOVE THE WIRE FROM THE WIRE WRAP POSTS WITH THE SPECIAL TOOLS
_______ MADE FOR THAT PURPOSE AS IDENTIFIED IN CHAPTER 20 OF THE WIRING DIAGRAM MANUAL. IF YOU DO NOT USE THE CORRECT TOOLS YOU CAN CAUSE DAMAGE TO THE WIRE WRAP POSTS.
 (8)  
Remove the wire from the wire wrap posts with the instructions in the Wiring Diagram Manual, Chapter 20.

 S 422-022

 (9)  
Install the wire on the wire wrap posts with the instructions in the Wiring Diagram Manual, Chapter 20.

 S 412-023

 (10)
 Install the post cover on the wire wrap posts.

 S 412-024

 (11)
 Install the WIU cover on the applicable electronic shelf (View B, Fig. 201):

 (a)  
Put the WIU cover on the unit.

 (b)  
Install the bolts.

 S 092-025
 (12)
 Remove the ESD wrist strap from the electrostatic ground receptacle on the WIU rack (Fig. 201).

 S 092-026

 (13)
 Remove the ESD wrist strap from your wrist.

 NOTE: Put the ESD wrist strap in one of the empty bags that are at
____ the ends of the WIU rack (Fig. 201).
 S 412-027
 (14) Install the cargo lining on the aft side of the electronic rack:
 (a)  
Put the cargo lining in its position.

 (b)  
Install the bolts.

 TASK 20-41-03-762-028
 4. Check - WIUs for Continuity (Fig. 201)
___________________________
 A. General
 (1)  
Do this check when there are wiring problems that you could not find with the power and signals check procedure. Or do this check after you have repair the wire wrap.
　
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