Deactivation of the No. 1 Bearing Vibration Sensor [CFMI]

TASK 77-31-00-040-801-A
Deactivation of the No. 1 Bearing Vibration Sensor

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

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.

1. Reason for the Job
To keep the engine serviceable and to make subsequent flights possible after you find that the No. 1 bearing vibration sensor is not serviceable. The vibration indications in the cockpit will come from the vibration sensor of the Turbine Rear Frame (TRF) until the No. 1 bearing vibration sensor is replaced at the first engine shop visit.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	CAP - BLANKING, PLASTIC
No specific	1	COVER - PROTECTION
No specific	1	PLUG - BLANKING, PLASTIC
No specific	1	TAPE - ADHESIVE
No specific	1	TIE WRAP(S)
No specific	AR	WARNING NOTICE(S)

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.05RAR8)	Adhesive Film Tape-- Film Polyethylene Legacy 2
(Material No.05RQB9)	Adhesive Film Tape-Erosion Protective Polyurethane - 0.36mm Legacy
(Material No.05TAB1)	Adhesive Tape-- Glass Cloth -
(Material No.05TKB1)	Adhesive Tape-Electrical Insulation Glass Cloth -
(Material No.05WBA1)	Adhesive Primer-Pressure Sensitive Adhesive - -
(Material No.14JAB1)	Sealing Profile-- Silicone Foam -

C. Work Zones and Access Panels

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

D. Referenced Information

REFERENCE	DESIGNATION
TASK 71-13-00-010-040-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-040-A	Closing of the Fan Cowl Doors
TASK 77-32-34-869-041-A	Change the configuration of the Accelerometer
Locations for the Deactivation of the No. 1 Bearing Vibration Sensor

3. Job Set-up
Subtask 77-31-00-941-051-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) On the center pedestal, on ENG panel 115VU:
(a) Put a WARNING NOTICE(S) in position to tell persons not to start the engine.
(2) Make sure that the engine 1(2) shutdown occurred not less than five minutes before you do this procedure.
(3) On 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) in position to tell persons not to energize FADEC 1(2).

Subtask 77-31-00-010-051-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

4. Procedure
Subtask 77-31-00-040-051-A ** ON A/C NOT FOR ALL

A. Deactivation of the No. 1 Bearing Vibration Sensor
(1) Disconnect the vibration sensor harness from the No. 1 bearing vibration sensor.
(2) Prepare the connector of the vibration sensor harness for storage:
(a) Install a locally manufactured jumper wire between pin 2 and pin 3.
(b) Safety the jumper wire with TAPE - ADHESIVE and lock it with a PLUG - BLANKING, PLASTIC.
(c) Install a COVER - PROTECTION on the connector and safety it with TAPE - ADHESIVE.
(3) To isolate the area of the connector of the vibration sensor harness, install Adhesive Film Tape-- Film Polyethylene Legacy 2 (Material No.05RAR8) or Adhesive Film Tape-Erosion Protective Polyurethane - 0.36mm Legacy (Material No.05RQB9) or Sealing Profile-- Silicone Foam - (Material No.14JAB1) or Adhesive Primer-Pressure Sensitive Adhesive - - (Material No.05WBA1) or Adhesive Tape-Electrical Insulation Glass Cloth - (Material No.05TKB1) or Adhesive Tape-- Glass Cloth - (Material No.05TAB1) .
(4) Attach and safety the vibration sensor harness to the thrust reverser harness with a TIE WRAP(S) to prevent chafing of harnesses against each other.
(5) On the connector of the No. 1 bearing vibration sensor, install a CAP - BLANKING, PLASTIC. Attach a COVER - PROTECTION with a TIE WRAP(S) on its outer diameter.
(6) Make sure that "TRF" is selected as the active engine vibration accelerometer (Ref. AMM TASK 77-32-34-869-041) and that no frequency analysis on the No.1 bearing is automatically printed during the flight. If different, check the installation of the jumper wire, brackets of wires and connectors.

5. Close-up
Subtask 77-31-00-410-051-A ** ON A/C NOT FOR ALL

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-040):
(a) FOR [1000EM1] (ENGINE-1)
437AL 438AR
(b) FOR [1000EM2] (ENGINE-2)
447AL 448AR
(3) Remove the WARNING NOTICE(S).
(4) Make an entry in the logbook.

[Rev.10 from 2021] 2026.04.02 07:41:14 UTC