Visual Examination of the FADEC System Wiring Harnesses (Ground Harness Check) [PW11]

TASK 73-21-00-200-805-A
Visual Examination of the FADEC System Wiring Harnesses (Ground Harness Check)

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 400

1. Reason for the Job
Use this procedure to inspect electrical harnesses for loose backshells, worn insulation, missing or bent pins and general serviceable condition.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 1M(3 FT)
No specific	1	PLIERS - JAWED, SOFT

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR, 451AL, 452AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR, 461AL, 462AR

C. Expendable Parts

FIG.ITEM	DESIGNATION	IPC-CSN
510	PRESSURE SENSITIVE ADHESIVE-TAPE	EIPC 73-21-63-01-510
530	PRESSURE SENSITIVE ADHESIVE-TAPE	EIPC 73-21-63-01-530

D. Referenced Information

REFERENCE	DESIGNATION
TASK 26-12-61-000-802-A	Removal of the Loop-A Fire Electrical Harness and the Loop-A Fire Detector Cables
TASK 26-12-61-400-802-A	Installation of the Loop-A Fire Electrical Harness and the Loop-A Fire Detector Cables
TASK 26-12-62-000-802-A	Removal of the Loop-B Fire Harness
TASK 26-12-62-400-802-A	Installation of the Loop-B Fire Harness
TASK 70-70-00-910-802-A	Installation of the Wiring Harnesses
TASK 71-00-00-860-832-A	Procedure to Prevent Engine Motoring and to Stop the Electrical Supply to the EEC
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-802-A	Closing of the Fan Cowl Doors
TASK 72-62-00-210-802-A	General Visual Inspection (GVI) of the Angle Gearbox
TASK 73-21-00-300-801-A	Repair of Frayed Harness - Full Authority Digital Engine Control (FADEC) System
TASK 73-21-61-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (WF01)
TASK 73-21-61-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (WF01)
TASK 73-21-62-000-802-A	Removal of the EEC Wiring Harness (WF02)
TASK 73-21-62-400-802-A	Installation of the EEC Wiring Harness (WF02)
TASK 73-21-63-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (W03)
TASK 73-21-63-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (W03)
TASK 73-21-64-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (W04)
TASK 73-21-64-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (W04)
TASK 73-21-66-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (WF06)
TASK 73-21-66-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (WF06)
TASK 73-21-67-000-801-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (WF07)
TASK 73-21-67-400-801-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (WF07)
TASK 73-21-68-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (WC08)
TASK 73-21-68-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (WC08)
TASK 73-21-69-000-802-A	Removal of the EEC Wiring Harness (WC10)
TASK 73-21-69-400-802-A	Installation of the EEC Wiring Harness (WC10)
TASK 73-21-70-000-802-A	Removal of the Electronic Engine Control (EEC) Wiring Harness (WC11)
TASK 73-21-70-400-802-A	Installation of the Electronic Engine Control (EEC) Wiring Harness (WC11)
TASK 73-25-34-400-802-A	Installation of the Engine Interface Unit (EIU)
TASK 77-21-61-000-802-A	Removal of the Exhaust Gas Temperature (EGT) (T5/T3) Wiring Harness (WC05)
TASK 77-21-61-400-802-A	Installation of the Exhaust Gas Temperature (EGT) (T5/T3) Wiring Harness (WC05)
TASK 78-30-00-040-805-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-805-A	Reactivation of the Thrust Reverser System after Ground Maintenance
TASK 78-36-00-010-802-A	Opening of the Thrust Reverser Cowl-Doors
TASK 78-36-00-410-802-A	Closing of the Thrust Reverser Cowl-Doors
FADEC System Wiring Harness (Fan Case Harnesses)
Visual Examination of FADEC System Wiring Harness (Core Harnesses)
Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses)
Visual Examination of FADEC System Wiring Harness (Core Harnesses)

3. Job Set-up
Subtask 73-21-00-941-061-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Make sure that you did the procedure to prevent engine motoring and to stop the electrical supply to the Electronic Engine Control (EEC)
(Ref. AMM TASK 71-00-00-860-832).

Subtask 73-21-00-010-061-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(2) Put the ACCESS PLATFORM 1M(3 FT) in position.

Subtask 73-21-00-040-055-A ** ON A/C NOT FOR ALL

C. Deactivation of the Thrust Reverser for Maintenance

WARNING: YOU MUST DEACTIVATE THE THRUST REVERSER BEFORE YOU DO WORK ON OR AROUND IT. IF YOU DO NOT, THE THRUST REVERSER CAN OPERATE ACCIDENTALLY AND CAUSE AN INJURY AND/OR DAMAGE.

(1) Do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-805).

Subtask 73-21-00-010-062-A ** ON A/C NOT FOR ALL

D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.

4. Procedure

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

Subtask 73-21-00-200-050-A ** ON A/C NOT FOR ALL

A. Do an inspection of the electrical connectors on each harness as follows:

FADEC System Wiring Harness (Fan Case Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of FADEC System Wiring Harness (Core Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of FADEC System Wiring Harness (Core Harnesses) ** ON A/C NOT FOR ALL

(1) Make sure that the connector coupling nut is tight when you push it rearward and forward.
(2) Make sure that the backshell coupling nut is tight on the connector when you push it rearward and forward.
(3) Make sure that there is no movement of the harness in the backshell clamps and that the clamp screws are tight.
(4) Make sure that you tighten the nuts of the connectors with the stud/lug configurations, but do not tighten them with too much force.
(5) Examine the harness for cuts, chafing or other obvious damage or deterioration.
(a) If you find damage (Ref. AMM TASK 73-21-00-300-801) for damage limits and repairs.
(6) Do the inspection of the connectors, receptacles, capture plates and backshells. See table 1.

Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses) ** ON A/C NOT FOR ALL

EXAMINE	DAMAGE	DISPOSITION
Connector for:
Knurled coupling ring for:	Scratches or gouges on non seal surfaces no more than 0.010 IN. (0.254 MM) deep	Permitted
	Cracks	Not permitted
Front face inner ring for:	Any damage	Not permitted
Master keyway and keys for:	Missing keys	Not permitted
Front grommet (rigid dielectric material) for:	Small chips no more than 0.001 in.2 (0.645 mm2) that are less than 0.04 IN. (1.02 MM) from a socket contact or the edge	Permitted
Socket contact for:	Pushed in socket contact	Not permitted
Electromagnetic Interference (EMI) spring fingers for:	Bent or missing spring finger	Not permitted
Receptacle for:
Front face inner ring for:	Scratches or gouges on non seal surfaces no more than 0.010 IN. (0.254 MM) deep	Permitted
	Cracks	Not permitted
Front grommet (soft seal material) for:	Any damage	Not permitted
Pin contact for:	Bent, pushed back, or missing pin contact	Not permitted
Coupling thread for:	Dents, scratches, or gouges no more than 0.010 IN. (0.254 MM) deep as long as damage does not prevent mating	Permitted
Backshell for:
Shell for:	Dents, scratches, or gouges no more than 0.010 IN. (0.254 MM) deep as long as damage does not prevent mating	Permitted
	Cracks	Not permitted
Coupling nut for:	Loose coupling nut	Not permitted
Capture plate for:
Plate for:	Dents, scratches, or gouges no more than 0.010 IN. (0.254 MM) deep	Permitted
	Cracks	Not permitted
	Heat discoloration	Not permitted
	Missing anchor nut	Not permitted
	Bent or missing retaining flange	Not permitted

Table - Harness Inspection Limits

(a) Do the inspection of the harness and the endpoint identification as follows:

Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses) ** ON A/C NOT FOR ALL

1 Make sure that the marking can be seen clearly.
(b) Do the inspection of the Functional Item Number (FIN) marker as follows.
(Ref. AMM TASK 73-21-00-300-801) for repairs.
1 Make sure that no less than one marking can be seen clearly.
2 Make sure that the FIN marker is tight on the bundle and does not turn or move freely along the bundle.
(7) Do the inspection of the W03 harness near the angle gearbox for evidence of chafing or wear.

Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses) ** ON A/C NOT FOR ALL

(8) Do an inspection of the branch of the harness (W03) that connects to the auxiliary oil pressure sensor for chafing or wear (Ref. AMM TASK 73-21-00-300-801).
(9) If damage exists to the harness (W03) braided shield and does not continue into the electrical wire coat, wrap and tape the harness at the damaged area (Ref. AMM TASK 73-21-00-300-801).
(10) If you find damage of the harness (W03) internal electrical wires, replace the harness (Ref. AMM TASK 73-21-63-000-802) and (Ref. AMM TASK 73-21-63-400-802).
(11) Do the inspection of the angle gearbox for wear from harness (W03) chafing (Ref. AMM TASK 72-62-00-210-802).
(12) Do an inspection of the bracket for cracks.
(a) If there is damage to the bracket, replace the bracket.
(13) Make sure that all the harness braided shields that terminate on the backshell are tight in the clamp.

FADEC System Wiring Harness (Fan Case Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of FADEC System Wiring Harness (Core Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of the FADEC System Wiring Harnesses - (Fan Case Harnesses) ** ON A/C NOT FOR ALL

Visual Examination of FADEC System Wiring Harness (Core Harnesses) ** ON A/C NOT FOR ALL

(14) Tighten all loose electrical connectors as follows:
(a) Examine, align and engage the connector.
(b) Push lightly in the connector while you tighten the coupling ring.
(c) Use the PLIERS - JAWED, SOFT and tighten the connector against the receptacle.
(d) Make sure that you can feel the ratchet feature.
(e) While you tighten, push the connector in and from side to side.
(f) Tighten the connector until the PLIERS - JAWED, SOFT slip on the connector ring.
(15) For additional information on wiring harness installation (Ref. AMM TASK 70-70-00-910-802).
(16) If necessary, replace the (WF01) fan harness (4217KS) (Ref. AMM TASK 73-21-61-000-802) and (Ref. AMM TASK 73-21-61-400-802).
(17) If necessary, replace the (WF02) fan harness (4218KS) (Ref. AMM TASK 73-21-62-000-802) and (Ref. AMM TASK 73-21-62-400-802).
(18) If necessary, replace the (W03) harness (4087KS) (Ref. AMM TASK 73-21-63-000-802) and (Ref. AMM TASK 73-21-63-400-802).
(19) If necessary, replace the (W04) harness (4088KS) (Ref. AMM TASK 73-21-64-000-802) and (Ref. AMM TASK 73-21-64-400-802).
(20) If necessary, replace the (WC05) (EGT T5/T3) harness (Ref. AMM TASK 77-21-61-000-802) and (Ref. AMM TASK 77-21-61-400-802).
(21) If necessary, replace the (WF06) harness (4089KS) (Ref. AMM TASK 73-21-66-000-802) and (Ref. AMM TASK 73-21-66-400-802).
(22) If necessary, replace the (WF07) harness (4093KS) (Ref. AMM TASK 73-21-67-000-801) and (Ref. AMM TASK 73-21-67-400-801).
(23) If necessary, replace the (WC08) harness (4094KS) (Ref. AMM TASK 73-21-68-000-802) and (Ref. AMM TASK 73-21-68-400-802).
(24) If necessary, replace the (WC10) harness (4011KS) (Ref. AMM TASK 73-21-69-000-802) and (Ref. AMM TASK 73-21-69-400-802).
(25) If necessary, replace the (WC11) harness (4072KS) (Ref. AMM TASK 73-21-70-000-802) and (Ref. AMM TASK 73-21-70-400-802).
(26) If necessary, replace the engine core fire detector (Loop B) harness (4000WD2) (Ref. AMM TASK 26-12-62-000-802) and (Ref. AMM TASK 26-12-62-400-802).
(27) If necessary, replace the engine core fire detector (Loop A) harness (4004WD1) (Ref. AMM TASK 26-12-61-000-802) and (Ref. AMM TASK 26-12-61-400-802).
(28) Examine the assembly for foreign objects, damage, and correct assembly.

Subtask 73-21-00-210-058-A ** ON A/C NOT FOR ALL

B. General Harness Handling Requirements
(1) Remove all the twists, bends or deformations introduced during shipping or storage. The protective caps or covers must stay with the harness until the connection with the mating components is ready to be made.
(2) General positioning, handling and installation:
(a) Be careful when you install and adjust the harnesses in their clips to prevent damage to the overbraid of the harnesses. Do not pull the harnesses through the clips. If necessary, remove the harnesses from the clips and install them again.
(b) Be careful when you pull the wire harness through the access areas or along other hardware to prevent damage.
(c) Sharp bends are not permitted in the harness at the clips, clamps and connector backshells. The harness must not be kinked.
(d) Branch breakouts (where the overbraid diameter is larger because of the start of a new harness leg) must be at a minimum distance of 1.5 IN. (38.1 MM) from the clips.
(e) Harness to component connection:
1 Before you connect the harness, make sure the connector pins and sockets have no damage.
2 Make sure that the master keyways are aligned before you connect the connectors. If the connector is not fully installed, do not turn the connector to get the keyway alignment.
3 After master keyways are aligned, lightly push connectors in and from side to side while you tighten the coupling ring until it is fully installed. If the coupling ring stops, or cannot be hand-tightened until it is fully installed, loosen the coupling ring, disconnect the connectors, and examine the contacts.
4 For all the engine interface connectors, after you fully install the coupling ring by hand, do as follows:
a Use the connector pliers to apply the final torque. Turn the connector until you feel that the connector pliers slip on the connector ring.

Use the connector pliers for the electronic engine control, prognostic health metering unit, and exciter connections.

b For those engine interface connectors where the connector pliers cannot be used, move the backshell and the harness assembly side to side to check for correct installation. There must be no movement with relation to the connector.
(f) Make sure that the tension in the harnesses is correct.
(3) Installation of the harnesses in spring clips:
(a) If the harness is not aligned with the spring clips or the spring clip cuts into the harness, do the steps that follow:
1 Adjust the harness tension so that it aligns with the spring clips and does not pull out from the clip.
2 If the harness is not correctly aligned after adjustment, wind the EIPC 73-21-63-01-510 PRESSURE SENSITIVE ADHESIVE-TAPE (510) around the harness to give a tighter fit and to prevent harness damage as follows:

NOTE: It is permitted to use the EIPC 73-21-63-01-530 PRESSURE SENSITIVE ADHESIVE-TAPE (530) as an alternative tape.

a Record the spring clip location on the harness and remove the harness from the spring clip.
b Wind the pressure sensitive adhesive-tape around the harness at a distance of 0.5 IN. (12.7 MM) - 1.5 IN. (38.1 MM) from one side of the spring clip location.
c Apply the pressure sensitive adhesive-tape with an overlap of approximately 50 per cent. If available, use the colored guideline in the center of the pressure sensitive adhesive-tape as a guide.
d Continue to wind the pressure sensitive adhesive-tape to 0.5 IN. (12.7 MM) - 1.5 IN. (38.1 MM) more than the spring clip location on the opposite side.
e Use the hand pressure to attach the cut end of the pressure sensitive adhesive-tape to the last wind of tape.
f Install the harness on the spring clip.
(b) Apply the pressure sensitive adhesive-tape on the harness as necessary to prevent it from being loose in the spring clips.
(4) Electrical harness routing criteria:
(a) The cables must be supported to prevent chafing.
(b) The harnesses with non-metallic chafe guard (peek or nomex overbraid) must not contact the components that follow:
1 The hot air lines (turbine cooling, anti-ice, pb (p3))
2 The fabric, composite, or metal bellows
3 The sharp edges (including all the bracket break edges)
4 The metal overbraid harness
5 The flex hose or hose section of tube or hose assemblies.
(c) The harnesses with metallic chafe guard overbraid must not contact adjacent hardware.
(d) If contact is found, the harness tension must be adjusted to eliminate contact.
(e) If the harness still makes contact with the components after adjustment, then wind the harness with the pressure sensitive adhesive-tape as follows:
1 Record the spring clip location on the harness and remove the harness from the spring clip.
2 Remove the harness from the spring clip as necessary.
3 Wind the pressure sensitive adhesive-tape around the harness at a distance of 0.5 IN. (12.7 MM) - 1.5 IN. (38.1 MM) from one side of the spring clip location.
4 Apply the pressure sensitive adhesive-tape with an overlap of approximately 50 per cent. If available, use the colored guideline in the center of the pressure sensitive adhesive-tape as a guide.
5 Continue to wind the pressure sensitive adhesive-tape to 0.5 IN. (12.7 MM) - 1.5 IN. (38.1 MM) more than the spring clip location on the opposite side.
6 Use the hand pressure to attach the cut end of the pressure sensitive adhesive-tape to the last wind of tape.
7 Install the harness on the spring clip, if removed.
(5) The ignition cables must be supported during the engine tests where the Engine Build-up Unit (EBU) is not installed.

5. Close-up
Subtask 73-21-00-410-057-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 cowl-doors (Ref. AMM TASK 78-36-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
451AL, 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
461AL, 462AR.
(3) Make sure that all the circuit breakers shown in the paragraph Procedure of the engine interface unit installation are closed. If they are not, close them in the recommended sequence
(Ref. AMM TASK 73-25-34-400-802).

Subtask 73-21-00-440-055-A ** ON A/C NOT FOR ALL

B. Do the reactivation of the thrust reverser system after maintenance (Ref. AMM TASK 78-30-00-440-805).

Subtask 73-21-00-410-058-A ** ON A/C NOT FOR ALL

C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 03:02:38 UTC