Removal of the Prognostics and Health Management Unit (PHMU) [PW11]

TASK 77-31-01-000-801-A
Removal of the Prognostics and Health Management Unit (PHMU)

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS INSTRUCTION, INJURY CAN OCCUR.

ZONE: 400
FIN: 4609KS ** 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	1	ACCESS PLATFORM 1M(3 FT)
No specific	AR	COVER - PROTECTION
No specific	1	PLIERS - JAWED, SOFT
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
400	POWER PLANT, NACELLES AND PYLONS
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL, 448AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-860-832-A	Procedure to Prevent Engine Motoring and to Stop the Electrical Supply to the EEC
TASK 71-13-00-010-802-A	Opening of the Fan Cowl Doors
Prognostics and Health Management Unit (PHMU)

3. Job Set-up
Subtask 77-31-01-941-050-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) Do the procedure to prevent engine motoring and to stop the electrical supply to the Electronic Engine Control (EEC)
(Ref. AMM TASK 71-00-00-860-832).

Subtask 77-31-01-010-050-A ** ON A/C NOT FOR ALL

B. Get Access
(1) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-802):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENG 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENG 2)
447AL 448AR
(2) Put an ACCESS PLATFORM 1M(3 FT) in position.

Subtask 77-31-01-865-050-A ** ON A/C NOT FOR ALL

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
FOR FIN: 4020KM1 (POWER PLANTDEMOUNTABLE, ENG 1)
121VU	PHMU/ENG1	95KS1	P44
FOR FIN: 4020KM2 (POWER PLANTDEMOUNTABLE, ENG 2)
121VU	PHMU/ENG2	95KS2	P45

4. Procedure

CAUTION: WIPE CLEAN ALL PARTS AND TOOLS AS NECESSARY TO REMOVE UNWANTED DEBRIS AND PREVENT DAMAGE TO THE ENGINE.

Subtask 77-31-01-020-050-A ** ON A/C NOT FOR ALL

A. Removal of the Prognostics and Health Management Unit (PHMU)
(1) Find the PHMU (1) attached to the fan case at the 2 o'clock position. See the sheet 1 of the figure.
(2) Remove the PHMU (1) from the fan case brackets as follows:
(a) Remove the bolts (2) that connect the ground strap to the PHMU (1).
(b) Disconnect the wiring harnesses (WF02) and (W03) connectors (P9) and (P10) from the PHMU (1) with the PLIERS - JAWED, SOFT. See the sheet 2 of the figure.
(c) Remove the four bolts (12).
(d) Remove the PHMU (1) from the fan case brackets.
(3) Installation of the protection covers

CAUTION: INSTALL PROTECTION COVERS ON ALL THE OPENINGS IMMEDIATELY TO PREVENT DAMAGE TO THE ENGINE.

(a) Make sure that you install COVER - PROTECTION as necessary to prevent damage to the engine.

[Rev.10 from 2021] 2026.04.01 13:06:41 UTC