Removal of the Electronic Control Unit (ECU) Channel B Harness 238W0904 [CFMI]

TASK 71-51-44-000-005-A
Removal of the Electronic Control Unit (ECU) Channel B Harness 238W0904

FIN: 1000EM1 ** ON A/C NOT FOR ALL
FIN: 1000EM2 ** ON A/C NOT FOR ALL

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	COVER - PROTECTION
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-A	Opening of the Fan Cowl Doors
ECU Channel B Harness

3. Job Set-up
Subtask 71-51-44-941-054-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 71-51-44-865-062-A ** ON A/C NOT FOR ALL

WARNING: OPEN THE PROBE HEATER CIRCUIT-BREAKERS 1DA1(2), 3DA1(2,3), 4DA1(2,3) AND 5DA1(2,3) BEFORE ENG1(2)FADEC A and EIU 1(2) C/B'S 2KS1 AND 2KS2. IF YOU DO NOT OBEY THIS SEQUENCE:

THE PROBES WILL BECOME TOO HOT.
THIS CAN CAUSE DAMAGE TO EQUIPMENT AND INJURY TO MAINTENANCE PERSONNEL.

B. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	ENGINE/1 AND 2/IGN/SYS A	1JH	A03
49VU	ANTI ICE/PROBES/AOA/1	4DA1	D04
49VU	ANTI ICE/PROBES/PITOT/1	3DA1	D02
49VU	COM/CVR/SPLY	2RK	E14
49VU	COM/CVR/CTL	4RK	E13
121VU	RCDR/DFDR	7TU	K16
121VU	HYDRAULIC/HYD POWER/Y	3803GX	N30
122VU	ANTI ICE/WINDOWS/R	4DG2	W14
122VU	ANTI ICE/WINDOWS/L	4DG1	X14
122VU	ANTI ICE/PROBES/2/PITOT	3DA2	Y14
122VU	ANTI ICE/PROBES/2/AOA	4DA2	Y13
122VU	ANTI ICE/PROBES/2/STATIC	5DA2	Y11
122VU	ANTI ICE/PROBES/3/PITOT	3DA3	Z16
122VU	ANTI ICE/PROBES/3/AOA	4DA3	Z15
122VU	ANTI ICE/PROBES/3/STATIC	5DA3	Z14
122VU	ANTI ICE/PROBES/1/STATIC	5DA1	Z13
123VU	Y HYD/ELEC/PUMP	3802GX	AB06
123VU	Y HYD/ELEC/ELEC PUMP/NORM	3801GX	AB03
FOR FIN: 1000EM1 (ENGINE1)
49VU	ENGINE/1/FIRE DET/LOOP A	7WD1	A06
49VU	ENGINE/1/FADEC A/AND EIU 1	2KS1	A04
121VU	ENGINE/IGN/ENG1/SYS B	3JH1	P41
121VU	ENGINE/IGN/ENG1/SYS A BAT	2JH1	P39
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/B	2WE1	Q44
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL1/SQUIB/A	1WE1	Q43
121VU	ENGINE/ENG1/FIRE DET/LOOP B	8WD1	Q38
121VU	ENGINE/ENG1/FADEC B/AND EIU 1	4KS1	R41
122VU	ELEC/GCU/1	2XU1	T26
FOR FIN: 1000EM2 (ENGINE2)
49VU	ENGINE/2/FIRE DET/LOOP B	8WD2	A07
49VU	ENGINE/2/FADEC A/AND EIU 2	2KS2	A05
121VU	ENGINE/IGN/ENG2/SYS B	3JH2	P42
121VU	ENGINE/IGN/ENG2/SYS A BAT	2JH2	P40
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/B	2WE2	Q42
121VU	ENGINE/ENG1 AND 2 FIRE EXTIG/BTL2/SQUIB/A	1WE2	Q41
121VU	ENGINE/ENG2/FADEC B	4KS2	Q40
121VU	ENGINE/ENG2/FIRE DET/LOOP A	7WD2	Q39
122VU	ELEC/GCU/2	2XU2	T27

Subtask 71-51-44-010-058-A ** ON A/C NOT FOR ALL

C. 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.

4. Procedure
Subtask 71-51-44-020-054-A ** ON A/C NOT FOR ALL

A. Removal of the ECU Channel B Harness 238W0904

NOTE: To open the flip-lock clamps and hinged line blocks, turn the captive screws 1/4 screws turn counterclockwise to disengage the cam nut.

NOTE: Make sure you loosely install the hardware in the correct location after you remove the harness from the clamps and the line blocks.

(1) Disconnect electrical connectors 403VC-A and 407VC-A from the pylon junction box.
(2) Open the flip-lock clamps (10) and (15) and remove the harness (5) from the rubber inserts.
(3) Remove the screw (25), the washer (30) and the nut (35) that attach clamps (170) and (175) together (See Detail B).
(4) Remove the clamp (175) from the harness (5).

NOTE: Detail A shows the most current harness installation. Detail B illustrates the initial harness installation. Refer to the illustrated parts catalog for applicable harness installation configurations.

(5) Remove the screw (25), the washer (30) and the nut (35) that attach the clamps (20) and (40) together.
(6) Remove the clamp (20) from the harness (5).
(7) Remove the screws (25) and the washers (30) that attach the harness (5) to the bracket.
(8) Open the flip-lock clamp (45) and remove the harness (5) from the rubber insert.
(9) Open the line blocks (65) and remove the harness (5) from the rubber inserts.
(10) Remove the screw (25) that attach the clamp (50) to the bracket. Remove the clamp.
(11) Remove the screws (55) and the washers (30) from the line block (60).
(12) Remove the harness (5) from the rubber insert.
(13) Disconnect the electrical connector 4000JH2-A from the lower ignition exiter.

POST SB RA32071-81

(14) Remove the screw (25) and the washer (30) that attach the clamps (70) to the bracket. Remove the clamp.

END OF SB RA32071-81

(15) Remove the screws (80), the washers (30) and the nuts (35) from the line block (85).
(16) Remove the harness (5) from the rubber insert.
(17) Remove the screw (125), the washer (30), the spacer (95) and the nut (35) from the clamps (75), (90) and (100). Remove the clamp (90).
(18) Remove the hardware that attach the clamp (180) to the bracket below the ECU.

NOTE: The clamp (180) and the clamps shown in detail F was an installation change to prevent chafing. Initial harness installations did not have clamps at these locations. Refer to the illustrated parts catalog for applicable harness installation configurations.

(19) Disconnect the electrical connectors 4000KS-J2 and 4000KS-J4 from the ECU.
(20) Remove the screws (105) and (110) and the washers (30) from the line block (115).
(21) Remove the harness (5) from the rubber insert.
(22) Remove the screws (125) and (140), the washers (30) and the nuts (35) that attach the clamps (120) to the brackets. Remove the clamps from the harness (5).
(23) Remove the screw (130), the washer (30), the nut (35) and the spacer (135) that attach the clamps (120), (145) and (150) to the support tube.
(24) Remove the clamp (120) from the harness (5).
(25) Disconnect the electrical connector 4001EV-C from the gas generator speed sensor.
(26) Remove the screw (155), the washer (30), the spacer (135) and the clamp (120) that attach the harness to the bracket on flange station 199.
(27) Disconnect the electrical connector 4000EV-C from the fan speed sensor.
(28) Remove the screws (160) and the washers (30) from the line block (165).
(29) Remove the harness (5) from the rubber insert.
(30) Disconnect the electrical connector 4003VC-A from the transition box.
(31) Remove the electrical harness (5) from the engine.
(32) Put COVER - PROTECTION on the electrical connectors that follows:

the ECU
the pylon junction box
the lower ignition exciter
the generator speed sensor
the fan speed sensor
the transition box
the harness

[Rev.10 from 2021] 2026.04.01 12:55:04 UTC