Removal of the HJ4B Engine Wiring Harness [CFML]

TASK 73-21-60-000-807-A
Removal of the HJ4B Engine Wiring Harness

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

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

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	AR	CAP - PROTECTION
No specific	AR	COVER - PROTECTION
No specific	1	PLIERS - JAWED, SOFT
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 70-70-00-910-804-A	Electrical Standard Practices
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
HJ4B Engine Wiring Harness

3. Job Set-up
Subtask 73-21-60-941-065-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Make sure that the ENG/MODE selector switch is in the NORM position.
(b) Make sure that the ENG/MASTER 1(2) control switch was in the OFF position not less than five minutes before you do this procedure.
(c) Put WARNING NOTICE(S) in position to tell persons not to operate:

The ENG/MODE selector switch
The ENG/MASTER 1(2) control switch.

(2) On the ENG section of maintenance panel 50VU:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 73-21-60-010-068-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position.

4. Procedure
Subtask 73-21-60-020-058-A ** ON A/C NOT FOR ALL

A. Removal of the HJ4B Engine Wiring Harness

CAUTION: MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.

CAUTION: USE PLIERS THAT HAVE TEFLON JAWS TO TIGHTEN OR LOOSEN THE ELECTRICAL CONNECTORS. DO NOT USE PLIERS THAT HAVE METAL JAWS. METAL JAWS CAN CAUSE DAMAGE TO THE ELECTRICAL CONNECTORS.

(1) Disconnection of the HJ4B engine wiring harness (5) (Ref. AMM TASK 70-70-00-910-804):

NOTE: If necessary, use PLIERS - JAWED, SOFT to disconnect the electrical connectors.

(a) Disconnect the HJ4B engine wiring harness (5) connector from the EEC channel B J4 receptacle (at the three o'clock position).
(b) Disconnect the HJ4B engine wiring harness (5) electrical connector (6) from the pylon receptacle (1) (at the twelve o'clock position).
(c) Remove the bolt (3) that attaches the P-clamp (4) to the support bracket (2).
1 Remove the P-clamp (4) from the HJ4B engine wiring harness (5).
(d) Remove the bolt (8) that attaches the P-clamp (9) to the support bracket (11).
1 Remove the P-clamp (9) from the HJ4B engine wiring harness (5).
(e) Remove the HJ4B engine wiring harness (5) from the clip located on the support bracket (11).
(f) Remove the two bolts (14) that attach the electrical connector (21) to the bracket (19).
(g) Disconnect the electrical connector (21) from the bracket (19).
(h) Remove the two bolts (13) that attach the electrical connector (18) to the bracket (19).
(i) Disconnect the electrical connector (18) from the bracket (19).
(2) Remove the HJ4B engine wiring harness (5) from the seven clips (29) along its routing.
(3) Remove carefully the HJ4B engine wiring harness (5) from the engine.
(4) Install the COVER - PROTECTION and the CAP - PROTECTION on all the open ports, open tubes, open hoses and disconnected connectors.

[Rev.8 from Aug 2017] 2026.04.01 03:05:36 UTC