Harness Test (Menu Mode) [CFML]

TASK 73-29-00-740-801-A
Harness Test (Menu Mode)

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: YOU MUST NOT TOUCH HOT PARTS WITHOUT APPLICABLE GLOVES. HOT PARTS CAN CAUSE AN INJURY.

ZONE: 400

1. Reason for the Job
This test reports faults related to engine harnesses and electrical connector loss of signal connectivity. The operator shakes engine harnesses for up to 30 minutes during this test to detect up to 12 intermittent faults associated with loss of harness conduit connectivity. This is a non-motoring test. During the test, if the Electronic Engine Control (EEC) detects any faults, the Multipurpose Control and Display Unit (MCDU) screen is updated and displays fault information.
This task must be performed after a Trouble Shooting Manual (TSM) procedure.
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	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 31-32-00-860-012-A	Procedure to Get Access to the SYSTEM REPORT/TEST/ENG Page
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 78-30-00-040-809-A	Deactivation of the Thrust Reverser System for Ground Maintenance
TASK 78-30-00-440-809-A	Reactivation of the Thrust Reverser System after Ground Maintenance
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
Harness Test (Menu Mode)

3. Job Set-up
Subtask 73-29-00-861-061-A

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 73-29-00-941-057-A

B. 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, and
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 73-29-00-010-054-A

C. 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

Subtask 73-29-00-040-052-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.

D. Deactivation of the Thrust Reverser System for Maintenance

NOTE: Deactivation of the thrust reverser system is only required if troubleshooting harnesses is located in the core compartment.

(1) Do the deactivation of the thrust reverser system for maintenance (Ref. AMM TASK 78-30-00-040-809).

Subtask 73-29-00-010-055-A

E. Get Access

NOTE: Opening of the thrust reverser cowl-doors is only required if troubleshooting harnesses is located in the core compartment.

(1) Open the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-010-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

Subtask 73-29-00-865-067-A

F. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	ENGINE/1 AND 2/IGN/SYS A	1JH	A03
49VU	L/G/LGCIU/SYS1/NORM	1GA	C09
121VU	HYDRAULIC/LGCIU/SYS2	2GA	Q35
121VU	HYDRAULIC/LGCIU/SYS1/GRND SPLY	52GA	Q34
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENGINE 1)
49VU	ENGINE/1/FADEC A/AND EIU 1	2KS1	A04
121VU	ENGINE/IGN/ENG1/SYS B	3JH1	P41
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R40
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENGINE 2)
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
121VU	ENGINE/IGN/ENG2/SYS B	3JH2	P42
121VU	ENGINE/ENG2/FADEC B/AND EIU2	4KS2	R41

Subtask 73-29-00-941-058-A

G. Aircraft Maintenance Configuration
(1) On the ENG section of maintenance panel 50VU:

Release the FADEC GND PWR 1(2) pushbutton switch (the ON legend comes on).

(2) After the FADEC is energized, wait ten seconds before you start the test. If you do not wait ten seconds, the interactive mode stops the EEC self-test and this can cause unwanted faults.
(3) On the left or right Multipurpose Control and Display Unit (MCDU), get the SYSTEM REPORT/TEST/ENG page (Ref. AMM TASK 31-32-00-860-012).

4. Procedure
Subtask 73-29-00-750-050-A

A. Harness Test
(1) It is recommended that two technicians are available to perform this test:

One technician in the cockpit monitoring the MCDU screen for faults.
One technician at the engine manually manipulating the suspected harness(es).

(2) The technician in the cockpit should notify the technician at the engine immediately once a fault is detected so the proper harness and damage location can be identified.
(3) Only one harness should be manipulated at a time. It is recommended to begin from one end of the harness (EEC or component) and work towards the other end (whichever is easier).

NOTE: During the test, obey the instructions shown on the MCDU.

NOTE: The EEC will not enter the menu mode (interactive mode) after an enquire command from the CFDS (Centralized Fault Display System) when any of the following conditions are set:

N2 more than ten percent or invalid
Rotary selector on CRANK or IGN/START or invalid
Manual Start Button on ON or invalid
TLA (Throttle Lever Angle) not at idle or invalid
Aircraft in the air
MASTER lever ON or invalid
BITE command code input label invalid.

NOTE: The EEC will abort the Harness test and display the FUNCTION TERMINATED screen when any of the following conditions becomes set:

N2 more than ten percent or invalid
Engine not in default start state
TLA (Throttle Lever Angle) not at idle or invalid
MASTER lever ON or invalid
You enter in the interactive mode of the other channel
RETURN key is selected on the MCDU during a running test or special function.

NOTE: If one of the following conditions occurs while menu mode is active, the Menu Mode session will be exited directly, without displaying a specific screen:

RETURN key selected on main menu screen
Channel in Menu Mode is not the active channel
Invalid BITE command or Invalid equipment code received by EEC
A LOGOFF condition received by EEC
Engine start detected whereas function requiring idle speed (as Idle Test, Vibration Ground Run) is not active
Selected Mach > 0.12 or invalid
Aircraft indicates in air.

ACTION	RESULT
1.On the MCDU ENG page: Push the key adjacent to the FADEC XY indication. NOTE: Select only the channel which detected a fault during operation. NOTE: X for Engine, Y for Channel	The ENGINE X MAIN MENU is displayed. See sheet 1.
2.On the ENGINE X MAIN MENU: Push the key adjacent to the ENGINE TESTS indication.	The ENGINE TESTS screen is displayed. See sheet 2.
3.On the MCDU ENGINE TESTS main screen: Push the key adjacent to the HARNESS TEST indication.	HARNESS TEST is displayed. See sheet 2.
4.On the HARNESS TEST screen: Push the key adjacent to the PUSH BUTTON TO START THE TEST indication. NOTE: The EEC will automatically finish the test after 30 minutes by displaying the Harness Test No Faults screen.	When the start button is selected, the Harness TEST IN PROGRESS Screen is displayed. See sheet 3.
5.The technician at the engine manually moves the suspected harness(es) without removing them from their clips and support brackets. NOTE: Shake the harnesses near the connectors and between each harness support clamps/brackets. Inspect harnesses for signs of distress due to chafing and/or thermal damage. Harness distress can occur at harness supports such as clamps and brackets or where harnesses bend around tubes and components. NOTE: Verify the harness connectors are mated properly and that harnesses do not come into contact with external tubes or components except at harness mounting locations.	TEST IN PROGRESS is still displayed. If no faults are detected by the EEC, the Harness Test No Faults Recorded screen is displayed. See sheet 3.
A. If faults are detected, take appropriate action per the Trouble Shooting Manual (TSM).
B. To complete the test, select the key adjacent to PUSHBUTTON TO EXIT TEST as indicated in action 6.	If the EEC detects a fault, the Harness Test Fault Report screen is displayed. See sheet 3. NOTE: The EEC can detect up to 12 faults. Depending on the number of faults detected, the MCDU may present fault data on multiple pages. The EEC will stop monitoring the faults. If there are no fault, a "NO FAULT RECORDED" message will be displayed on the HARNESS TEST screen. If faults are found, the FAULT REPORT page will be displayed.
C. To abort the test, select RETURN.
6.On the MCDU: Push the key adjacent to the RETURN indication.	The Engine Tests Main screen is displayed.
7.On the Engine Test Main screen: Push the key adjacent to the RETURN indication.	The MCDU Home page is displayed.

(4) Do this procedure for each engine and channel that detected a fault during normal operation.
(5) On the MCDU, push the line key adjacent to the RETURN indication until the CFDS menu page comes into view.
(6) Stop the MCDU.

5. Close-up
Subtask 73-29-00-410-058-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Remove the access platform(s).
(3) Close the thrust reverser cowl-doors (Ref. AMM TASK 78-36-00-410-806):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
451AL 452AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
461AL 462AR

Subtask 73-29-00-440-052-A

B. Do the reactivation of the Thrust Reverser after maintenance (Ref. AMM TASK 78-30-00-440-809).

Subtask 73-29-00-410-059-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)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(2) Remove the WARNING NOTICE(S).

Subtask 73-29-00-860-084-A

D. Put the aircraft back to its initial configuration.
(1) On the overhead maintenance panel 50VU:

Push the ENG/FADEC GND PWR 1(2) pushbutton switch. The ON legend goes off.

Subtask 73-29-00-862-061-A

E. De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 03:06:00 UTC