Removal of the Upper Extension Lead [CFMB]

TASK 77-21-10-000-008-A
Removal of the Upper Extension Lead

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	CAP - BLANKING
No specific	AR	PLUG - BLANKING
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [1000EM1] (ENGINE-1)
437AL, 438AR, 451AL, 452AR
FOR [1000EM2] (ENGINE-2)
447AL, 448AR, 461AL, 462AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-B	Opening of the Fan Cowl Doors
TASK 78-30-00-481-041-B	Make the Thrust Reverser Unserviceable for Maintenance
TASK 78-36-00-010-040-B	Opening of the Thrust Reverser Doors
Upper Extension Lead

3. Job Set-up
Subtask 77-21-10-941-059-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 77-21-10-010-072-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors: (Ref. AMM TASK 71-13-00-010-040)
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR

Subtask 77-21-10-040-064-A ** ON A/C NOT FOR ALL

C. Make the thrust reverser unserviceable (Ref. AMM TASK 78-30-00-481-041).

Subtask 77-21-10-010-080-A ** ON A/C NOT FOR ALL

D. Open the thrust reverser doors: (Ref. AMM TASK 78-36-00-010-040)
(1) FOR [1000EM1] (ENGINE-1)
451AL 452AR
(2) FOR [1000EM2] (ENGINE-2)
461AL 462AR

4. Procedure
Subtask 77-21-10-020-057-A ** ON A/C NOT FOR ALL

A. Removal of the Upper Extension Lead.
(1) Cut and remove the lockwire.
(2) Disconnect the upper extension lead (10) from the upper right T495 sector junction box (120) and from the main junction box (20).
(3) Remove the parts which attach the upper extension lead (10) as follows:
(a) Remove the clamp(40).
(b) Remove the bolt (30) from the bracket (50) on flange S, at the 10:15 o'clock position (Detail C).
(c) Remove the clamp (70).
(d) Remove the bolt (60) from the bracket (80) on flange S, at the 11 o'clock position (Detail D).
(e) Remove the clamp (110).
(f) Remove the bolt (90) from the bracket (100) on flange S, at the 11:45 o'clock position (Detail E).
(4) Remove the upper extension lead from the engine.
(5) Install the PLUG - BLANKING and CAP - BLANKING on the connectors and receptacles.

[Rev.10 from 2021] 2026.04.01 13:00:15 UTC