Visual Inspection of the Core Electrical Harnesses [CFML]
TASK 71-52-43-210-801-A
Visual Inspection of the Core Electrical Harnesses
A. This procedure gives the instructions to do an inspection of the core electrical harnesses
B. The harnesses of the core include
A. Fixtures, Tools, Test and Support Equipment
B. Consumable Materials
C. Work Zones and Access Panels
D. Referenced Information
3. Job Set-up
Subtask 71-52-43-941-061-A
Subtask 71-52-43-210-051-A
Subtask 71-52-43-410-079-A
[Rev.10 from 2021]
2026.04.02 06:33:31 UTC
Visual Inspection of the Core Electrical Harnesses
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.
WARNING:
BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.
ZONE: 400
1. Reason for the JobA. This procedure gives the instructions to do an inspection of the core electrical harnesses
B. The harnesses of the core include
- Left (Channel A) Electrical Harness from the Pylon to the Core Fire Detector Elements (4204KS)
- Right (Channel B) Electrical Harness from the Pylon to the Core Fire Detector Elements (4205KS)
- Electrical Harness from the Pylon to the Environmental Control System (ECS) Valves (4228KS).
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | 1 | ACCESS PLATFORM 1M(3 FT) |
| No specific | AR | WARNING NOTICE(S) |
| REFERENCE | DESIGNATION |
|---|---|
| (Material No.CPNCL02662) | Isopropyl alcohol |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| 400 | POWER PLANT, NACELLES AND PYLONS |
| FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1) | |
| 437AL, 438AR, 451AL, 452AR | |
| FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2) | |
| 447AL, 448AR, 461AL, 462AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-803-A | Opening of the Fan Cowl Doors |
| TASK 71-13-00-410-803-A | Closing of the Fan Cowl Doors |
| TASK 71-52-43-000-803-A | Removal of the Electrical Harness from the Pylon to the Core Fire Detector Elements |
| TASK 71-52-43-000-804-A | Removal of the Electrical Harness from the Pylon to the Environmental Control System (ECS) Valves |
| TASK 71-52-43-400-803-A | Installation of the Electrical Harness from the Pylon to the Core Fire Detector Elements |
| TASK 71-52-43-400-804-A | Installation of the Electrical Harness from the Pylon to the Environmental Control System (ECS) Valves |
| TASK 78-30-00-040-807-A | Deactivation of the Thrust Reverser System for Nacelle Maintenance (ICU) |
| TASK 78-30-00-440-807-A | Reactivation of the Thrust Reverser System after Nacelle Maintenance (ICU) |
| TASK 78-36-00-010-806-A | Opening of the Thrust Reverser Cowl Doors |
| TASK 78-36-00-410-806-A | Closing of the Thrust Reverser Cowl Doors |
Subtask 71-52-43-941-061-A
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 the WARNING NOTICE(S) in position to tell persons not to operate:
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).
Subtask 71-52-43-010-097-A (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 the WARNING NOTICE(S) in position to tell persons not to operate:
- The ENG/MODE selector switch
- The ENG/MASTER 1(2) control switch.
(a) Make sure that the ON legend of the FADEC GND PWR/1(2) pushbutton switch is off.
(b) Put the WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).
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)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(c) Put an ACCESS PLATFORM 1M(3 FT) in position.
Subtask 71-52-43-040-078-A (1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(c) Put an ACCESS PLATFORM 1M(3 FT) in position.
C. Deactivation of the Thrust Reverser System for Maintenance
Subtask 71-52-43-010-098-A 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 nacelle maintenance (Ref. AMM TASK 78-30-00-040-807). D. Get Access
(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.
4. Procedure(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR.
Subtask 71-52-43-210-051-A
A. Visual Inspection of the Core Electrical Harnesses
(1) Do the visual inspection of the left (channel A) electrical harness for the core fire detector elements (1), right (channel B) electrical harness for the fire detector elements (2) and electrical harness for the Environmental Control System (ECS) Valves (3):
5. Close-up(1) Do the visual inspection of the left (channel A) electrical harness for the core fire detector elements (1), right (channel B) electrical harness for the fire detector elements (2) and electrical harness for the Environmental Control System (ECS) Valves (3):
| INSPECT/CHECK | MAXIMUM SERVICEABLE LIMITS | REMARKS |
|---|---|---|
| 1.Damage, cracking, missing rubber or swelling of the connector receptacle interfacial seal | Not serviceable. | If damaged, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-000-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
| 2.Contamination of the connector receptacle interfacial seal | Any amount that can be removed by Isopropyl alcohol (Material No.CPNCL02662) . | |
| 3.Signs of arcing or electrical failure on the electrical connectors and contacts | Not serviceable. | If damaged, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-000-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
| 4.Worn threads, stripped threads, corrosion or other damage on the connectors and back-shells | Not serviceable. | If damaged, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-400-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
| 5.Oil or dirt on exposed parts | Any amount that can be removed by cleaning with Isopropyl alcohol (Material No.CPNCL02662) . | |
| 6.Bent or broken pins | Not serviceable. | If damaged, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-000-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
| 7.Damaged polyether ether ketone or metal overbraid | Missing polyether ether ketone overbraid less than 0.5 in.2 (322.58 mm2) in area and less than 2.0 in. (50.80 mm) in length is permitted but should be repaired. Abraded areas on the metal overbraid under the polyether ether ketone are acceptable. Broken strands are acceptable as long as they do not create an exposure or hole larger than 0.1 in. (2.54 mm) in length or width. Exposure or hole up to 0.5 in. (12.70 mm) in length or width may be repaired. Reject the harness if there is any damage to the PTFE conductor insulation beneath the metal and fiberglass overbraid. Minor abrasion is acceptable providing the insulation layer is intact. | If overbraid is damaged within serviceable limits, repair (Ref. AMM D/O 71-51-43-30). If overbraid is damaged beyond serviceable limits, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-000-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
| 8.Dents, welds which have cracks or other damage | Not serviceable. | If damaged, replace the applicable electrical harness (Ref. AMM TASK 71-52-43-000-803) and (Ref. AMM TASK 71-52-43-400-803), (Ref. AMM TASK 71-52-43-000-804) and (Ref. AMM TASK 71-52-43-400-804). |
Subtask 71-52-43-410-079-A
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 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
461AL 462AR.
Subtask 71-52-43-440-064-A (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 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
461AL 462AR.
B. Do the reactivation of the thrust reverser system after nacelle maintenance (Ref. AMM TASK 78-30-00-440-807).
Subtask 71-52-43-410-080-A C. Close Access
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
(1) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
(POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR.
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
(POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(2) Remove the access platform(s).
(3) Remove the WARNING NOTICE(S).
Core Electrical Harnesses