(4)  
Open the thrust reversers (AMM 78-31-00/201).

 S 865-025-N00

 (5)  
Remove the electrical power (AMM 24-22-00/201).

 S 845-026-N00

 (6)  
Make sure that the engine shutdown was more than 5 minutes.

 F.
Do the Wire Harness Circuit Continuity Test

 S 035-027-N00
 (1)  Disconnect the two wire harness connectors which attach to the ends
 of the circuit where you will do a check.

 NOTE: Use a TG-70 or BT-BS-611 strap wrench, or equivalent
____ (Fig. 501). The rubber strap on the strap wrench will not hold the backshell if you apply too much force.
 S 485-028-N00
 (2)  
Attach an ohmmeter lead to the connector contacts at the ends of the circuit.

 (3)  
Measure the resistance.

 S 765-029-N00
 NOTE: If the shield resistance value is necessary, attach the
____
 ohmmeter leads to the connectors.

 (a)  The circuits must have continuity.
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ADAPTER
BACKSHELL
MASTER KEY
CONNECTOR
BT-BS-611 STRAP WRENCH CONNECTORBACKSHELL
TG-69 SOFT
TG-70
NOSE PLIERS
STRAP WRENCH
Backshell and Connector Tools
Figure 501

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C18888
////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
S 085-030-N00
 (4)  
Remove the ohmmeter leads from the harness connectors.

 G.
Do the Wire Harness Wire Insulation Check

 S 035-031-N00
 WARNING: DO NOT USE A MEGOHMMETER FOR THE INSULATION RESISTANCE TEST OF
_______
 THE ON-WING WIRE REPAIR. THIS COULD RESULT IN INJURY TO
 PERSONS OR DAMAGE TO THE AIRPLANE.

 CAUTION: YOU MUST DISCONNECT ALL THE CONNECTORS ON THE CIRCUIT WHICH YOU
_______
 WILL DO A CHECK. IF YOU DO NOT DO THIS, IT CAN CAUSE
 UNSATISFACTORY RESISTANCE INDICATIONS AND POSSIBLE DAMAGE TO
 THE CIRCUITS.

 (1)  Disconnect the wire harness connectors which attach to the ends of
 the circuits that you will do a test of.

 NOTE: Use a TG-70 or BT-BS-611 strap wrench, or equivalent
____
 (Fig. 501).

 S 765-032-N00
 (2)  Do these steps for a test of the insulation resistance:
 (a)  
Put the ohmmeter at the 100K ohms scale.

 (b)  
Attach one ohmmeter test lead to a connector contact (pin or socket) of the wire which you will test.

 (c)  
Connect the other test lead to the braided shield.

 (d)  
Measure the resistance.

 NOTE: The circuit resistance must be infinity.
____
 (e)  
Do the procedure again for the other wires you will do a test of.

 (f)  
Remove the ohmmeter leads.

 H. Connector/Receptacle Connection
 S 435-033-N00
 (1)  Connect the connectors to the receptacles.
 (a)  
Align the master key on the connector with the master key-way for the receptacle.

 (b)  
Engage the connector to the receptacle with light hand pressure.

 (c)  
Connect and tighten the connector coupling nut in a clockwise direction on the receptacle (Fig. 502 or 503).

 NOTE: Make sure the threads and contacts are correctly
____
 engaged.

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