Continuity Check-Power Plant Wire Harnesses Wires [CFMI]

TASK 71-50-00-280-040-A
Continuity Check-Power Plant Wire Harnesses Wires

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 1M(3 FT)
No specific	AR	MULTIMETER MODEL 160B
No specific	AR	OHMMETER MODEL 260
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-A	Closing of the Fan Cowl Doors
TASK 78-30-00-081-041-A	Make the Thrust Reverser Serviceable after Maintenance
TASK 78-30-00-481-041-A	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-36-00-010-040-A	Opening of the Thrust Reverser Doors
TASK 78-36-00-410-040-A	Closing of the Thrust Reverser Doors

3. Job Set-up
Subtask 71-50-00-941-057-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on the ENG panel 115VU:
(a) Put a WARNING NOTICE(S) to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(3) On the overhead maintenance panel 50VU:
(a) Make sure that the ON legend of the ENG/FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) to tell persons not to energize the FADEC 1(2).

Subtask 71-50-00-010-063-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-040):
(2) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(3) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(4) Put the ACCESS PLATFORM 1M(3 FT) in position.

Subtask 71-50-00-040-057-A ** ON A/C NOT FOR ALL

C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).

Subtask 71-50-00-010-066-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser doors (Ref. AMM TASK 78-36-00-010-040):
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR

4. Procedure
Subtask 71-50-00-280-052-A ** ON A/C NOT FOR ALL

A. Do a continuity check on any wire which seems to be unsatisfactory. Check the wire from one end to the other using either a MULTIMETER MODEL 160B or OHMMETER MODEL 260, or equivalent.

CAUTION: DO NOT CAUSE DAMAGE TO CONNECTOR PINS WHEN YOU DO CONTINUITY CHECKS. DAMAGED PINS CAN BECOME LOOSE AND CAN THUS INTERMITTENTLY PREVENT CORRECT CONTINUITY.

(1) Disconnect the connectors at each end of the wire harness which contains the unsatisfactory wire.
(2) Connect the leads of the multimeter or ohmmeter to each end of the wire and check the wire for continuity.
(3) Each circuit must have continuity from one end of the wire to the other end of the wire.
(4) Defective circuits must be repaired. Refer to the index at the beginning of Chapter 70 for the correct wire repair.

5. Close-up
Subtask 71-50-00-410-066-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the thrust reverser doors (Ref. AMM TASK 78-36-00-410-040):
(3) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(4) FOR [1000EM2] (ENGINE-2)
461AL 462AR

Subtask 71-50-00-440-057-A ** ON A/C NOT FOR ALL

B. Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-081-041).

Subtask 71-50-00-410-063-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl door (Ref. AMM TASK 71-13-00-410-040):
(2) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(3) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(4) Remove the access platform(s).
(5) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:23:07 UTC