Removal of the N2 Sensor [CFML]

TASK 77-11-10-000-802-A
Removal of the N2 Sensor

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.

FIN: 4065KS

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	CAP - PROTECTION
No specific	AR	COVER - PROTECTION
No specific	AR	WARNING NOTICE(S)

B. Work Zones and Access Panels

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

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
N2 Sensor

3. Job Set-up
Subtask 77-11-10-941-052-A

A. 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 77-11-10-010-055-A

B. 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 1M(3 FT) in position.

4. Procedure
Subtask 77-11-10-020-052-A

A. Removal of the N2 Sensor
(1) Disconnection of the harness electrical connectors

CAUTION: MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.

(a) Disconnect the HJ 6A harness electrical connector (3) from the N2 sensor (1).
(b) Disconnect the HJ6B harness electrical connector (4) from the N2 sensor (1).
(2) Remove the two bolts (5) that attach the N2 sensor (1) on the Transfer Gearbox (TGB) (2).
(3) Remove the N2 sensor (1) from the TGB (2).
(4) Clean the surfaces of unwanted materials.
(5) Remove and discard the O-ring (6) from the groove of the N2 sensor (1).
(6) Install COVER - PROTECTION and CAP - PROTECTION on all the open ports, open tubes, open hoses and connectors.

[Rev.10 from 2021] 2026.04.01 13:04:31 UTC