Removal of the Electronic Control Unit (ECU) Channel A Harness 238W0904 [CFMI]
TASK 71-51-44-000-004-A
Removal of the Electronic Control Unit (ECU) Channel A Harness 238W0904
1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment
B. Work Zones and Access Panels
C. Referenced Information
3. Job Set-up
Subtask 71-51-44-941-053-A ** ON A/C NOT FOR ALL
Subtask 71-51-44-010-056-A ** ON A/C NOT FOR ALL
Subtask 71-51-44-020-053-A ** ON A/C NOT FOR ALL
[Rev.10 from 2021]
2026.04.01 02:23:17 UTC
Removal of the Electronic Control Unit (ECU) Channel A Harness 238W0904
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) |
| ZONE/ACCESS | ZONE DESCRIPTION |
|---|---|
| FOR [1000EM1] (ENGINE-1) | |
| 437AL, 438AR | |
| FOR [1000EM2] (ENGINE-2) | |
| 447AL, 448AR | |
| REFERENCE | DESIGNATION |
|---|---|
| TASK 71-13-00-010-040-A | Opening of the Fan Cowl Doors |
Subtask 71-51-44-941-053-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 71-51-44-865-059-A ** ON A/C NOT FOR ALL (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).
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:
B. Open, safety and tag this(these) circuit breaker(s):- THE PROBES WILL BECOME TOO HOT.
- THIS CAN CAUSE DAMAGE TO EQUIPMENT AND INJURY TO MAINTENANCE PERSONNEL.
| 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 |
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(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.
Subtask 71-51-44-020-053-A ** ON A/C NOT FOR ALL
A. Removal of the ECU Channel A Harness 238W0904
(2) Remove the screw (20), the washers (25) and (35) and the nut (30) that attach clamp (40) to clamps (45). Remove the clamp.
(4) Remove the screw (20), the washer (25) and the nut (30) that attach the clamps (15) together. Remove the clamps from the harness (5).
(5) Remove the screws (20) and the washers (25) that attach the harness to the bracket.
(6) Remove the screws (50), the washers (25) and the clamps (55).
(7) Open the flip-lock clamp (60) and remove the harness (5) from the rubber insert.
(8) Remove the screws (70) and the washers (25) from the line block (75).
(9) Open the line blocks (65) along the flange station 167 and remove the harness (5) from the rubber inserts.
POST SB RA32071-81
(10) Remove the screw (20), the washer (25) and the nut (30) that attach the clamps (80) to the bracket near the anti-ice valve. Remove the clamp.
END OF SB RA32071-81
(11) Disconnect the electrical connector 4000JH1-A from the upper ignition exiter.
(12) Remove the screws (90), the washers (25) and the nuts (30) from the line block (95).
(13) Remove the harness (5) from the rubber insert.
(14) Open the line blocks (65) below the ECU and remove the harness (5) from the rubber inserts.
(15) Remove the screw (50), the washers (25) and (35) and the nut (30) from the clamps (85) and (115). Remove the clamps.
(16) Remove the screw (120), the washers (25) and (35) and the nut (30) from the clamps (85), (125) and (130).
(18) Remove the screws (100) and (105) and the washers (25) from the line block (110).
(19) Remove the harness (5) from the rubber insert.
(20) Disconnect the electrical connectors 4000KS-J1 and 4000KS-J3 from the ECU.
(21) Open the line blocks (65) along the flange station 191 and remove the harness (5) from the rubber inserts.
(22) Remove the screws (135) the washers (25) from the line block (140).
(23) Disconnect the electrical connector 4004VC-A from the transition box.
(24) Remove the electrical harness (5) from the engine.
(25) Put COVER - PROTECTION on the electrical connectors that follows:
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 402VC-A and 406VC-A from the pylon junction box. (2) Remove the screw (20), the washers (25) and (35) and the nut (30) that attach clamp (40) to clamps (45). Remove the clamp.
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.
(3) Open the flip-lock clamp (10) and remove the harness (5) from the rubber inserts. (4) Remove the screw (20), the washer (25) and the nut (30) that attach the clamps (15) together. Remove the clamps from the harness (5).
(5) Remove the screws (20) and the washers (25) that attach the harness to the bracket.
(6) Remove the screws (50), the washers (25) and the clamps (55).
(7) Open the flip-lock clamp (60) and remove the harness (5) from the rubber insert.
(8) Remove the screws (70) and the washers (25) from the line block (75).
(9) Open the line blocks (65) along the flange station 167 and remove the harness (5) from the rubber inserts.
POST SB RA32071-81
(10) Remove the screw (20), the washer (25) and the nut (30) that attach the clamps (80) to the bracket near the anti-ice valve. Remove the clamp.
END OF SB RA32071-81
(11) Disconnect the electrical connector 4000JH1-A from the upper ignition exiter.
(12) Remove the screws (90), the washers (25) and the nuts (30) from the line block (95).
(13) Remove the harness (5) from the rubber insert.
(14) Open the line blocks (65) below the ECU and remove the harness (5) from the rubber inserts.
(15) Remove the screw (50), the washers (25) and (35) and the nut (30) from the clamps (85) and (115). Remove the clamps.
(16) Remove the screw (120), the washers (25) and (35) and the nut (30) from the clamps (85), (125) and (130).
NOTE: The clamps shown in detail F was an installation change to prevent chafing. Initial harness installations did not have clamps at this location. Refer to the illustrated parts catalog for applicable harness installation configurations.
(17) Remove the clamp (130) from the harness (5). (18) Remove the screws (100) and (105) and the washers (25) from the line block (110).
(19) Remove the harness (5) from the rubber insert.
(20) Disconnect the electrical connectors 4000KS-J1 and 4000KS-J3 from the ECU.
(21) Open the line blocks (65) along the flange station 191 and remove the harness (5) from the rubber inserts.
(22) Remove the screws (135) the washers (25) from the line block (140).
(23) Disconnect the electrical connector 4004VC-A from the transition box.
(24) Remove the electrical harness (5) from the engine.
(25) Put COVER - PROTECTION on the electrical connectors that follows:
- the ECU
- the pylon junction box
- the upper ignition exciter
- the transition box
ECU Channel A Harness