Fault Message:

L ENG ACCELEROMETER/WIRING

Fault Code:

7735320BRV

Associated CAS:

None

This gives an indication that no vibration data is transmitted for the Left Engine.

• Engine Vibration Monitoring Unit (EVMU) (A42)
• Vibration Transducer
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

1. Open the circuit breakers that follow:

   System Name	Circuit Breaker Name	Bus Name
   ENGINE	L FADEC CH A	BATT
   ENGINE	L FADEC CH B	BATT
   ENGINE	L ENG IGN 1	BATT
   ENGINE	L ENG IGN 2	BATT
   ENGINE	L ENG FUEL HPSOV	BATT
   ENGINE	L ENG START A	BATT
   ENGINE	L ENG START B	BATT
   ENGINE	L T/R CTL VALVE	BATT
   ENGINE	L T/R LOWER LOCK	BATT
   ENGINE	L T/R UPPER LOCK	BATT

   WARNING: MAKE SURE THAT YOU DO A DEACTIVATION OF THE THRUST REVERSER BEFORE YOU DO WORK ON THE ENGINE. THE THRUST REVERSER CAN ACCIDENTALLY OPERATE. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO THE EQUIPMENT.

2. Perform a deactivation of the thrust reverser.
3. Get access to the EVMU to vibration transducer interface wiring and the EVMU (140BB access panel and 311BB access door).
4. Open the cowls.
   WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE DURING OR AFTER AN ENGINE OPERATION. THE ENGINE PARTS STAY HOT FOR APPROXIMATELY THREE HOURS AFTER THE ENGINE STOPS. THIS CAN CAUSE INJURY TO PERSONS.
   WARNING: BE CAREFUL IF YOU MUST DO WORK ON HOT COMPONENTS. USE APPROVED GLOVES AND PROTECTIVE CLOTHING. IF YOU DO NOT DO THIS, YOU CAN CAUSE INJURY TO PERSONS.
5. Disconnect the connectors P731, 1PA1, P627 and A42BP1.
6. Perform a visual inspection of the interface wiring and connectors for damage between the connectors vibration transducer (P731) and EVMU (A42BP1) (WM 71-50) (WM 77-31).
   NOTE: Look specially for signs of chafing adjacent to clip locations, condition of connector pins and wiring that is kinked or strained.

   1. If any damage is found, repair or replace the damage to continue with next step.
   2. If no damage is found, continue with next step.

7. Connect the connectors P731, 1PA1, P627 and A42BP1.
8. Check whether the fault message is stored or not.

   1. If YES, the fault message is stored, then the fault could be intermittent. Monitor the system to see if the fault message occurs again.

      1. If the fault message does not occur again, go to step 15.
      2. If the fault message occurs again, continue with next step.

   2. If NO, then the fault message is active, continue with next step.

9. Perform a continuity check between the connectors Vibration Transducer (P731) and Fixed Cowl Interface (1PA1).

   1. If there is no continuity, repair defective wiring as required and go to step 15.
   2. If there is continuity, continue with next step.

10. Perform wiring checks between Aft Pressure Bulkhead STN 861 LHS (P627) and Fixed Cowl Interface (1JA1).

    1. If wiring checks are not good, repair defective wiring as required and go to step 15.
    2. If wiring checks are good, continue with next step.

11. Perform wiring checks between Aft Pressure Bulkhead STN 861 LHS (J627) and EVMU (A42BP1).

    1. If wiring checks are not good, repair defective wiring as required and go to step 15.
    2. If wiring checks are good, continue with next step.

12. Replace vibration transducer.
13. Check whether the fault is active or not.

    1. If the fault is not active, go to step 15.
    2. If the fault remains active, continue with next step.

14. Replace the EVMU.
15. Close the cowls.
16. Activate the thrust reverser.
17. Do close out.