DOC AIRBUS | TSM A320FLoss of the N2 Vibration Indication on Engine 2
1. Possible Causes
· PMA-EEC ( 4005EV )
· EVMU ( 2EV )
· wiring from the EVMU (2EV) to the engine dedicated alternator stator (4005EV)
· Engine Dedicated Alternator (EDA) Drive Gear Assembly Retention Nut
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 24-41-00-861-002 Energize the Aircraft Electrical Circuits from the External Power
Ref. AMM 24-41-00-862-002 De-energize the Aircraft Electrical Circuits Supplied from the External
Power
Ref. AMM 31-60-00-860-002 EIS Stop Procedure
Ref. AMM 71-00-00-710-018 Discontinued Start, Restart and Shutdown Procedures
Ref. AMM 71-00-00-710-043 Normal Engine Automatic Start Procedure
Ref. AMM 71-00-00-710-047 Normal Engine Manual Start Procedure
Ref. AMM 72-60-33-200-011 Inspection of the Dedicated Alternator Drive Gear Assembly Retention
Nut
Ref. AMM 73-22-38-000-010 Removal of the Engine Dedicated Alternator (EDA) Stator and/or Cooling
Shroud
Ref. AMM 73-22-38-400-010 Installation of the Engine Dedicated Alternator (EDA) Stator and/or
Cooling Shroud
Ref. ASM 77-32-02
Ref. AMM 77-32-34-000-041 Removal of the Engine Vibration Monitoring Unit (EVMU)
REFERENCE DESIGNATION
Ref. AMM 77-32-34-400-041 Installation of the Engine Vibration Monitoring Unit (EVMU)
N2 Signal to EVMU (Engine 2) SHEET 1
Figure 77(IAE)-30-00-991-00400-A / SHEET 1/1 - N2 Signal to EVMU (Engine 2) not printed, as per
printing preferences
3. Fault Confirmation
Subtask 77-30-00-860-068-A
A. Job Set-up
(1) Energize the aircraft electrical circuits
Ref. AMM 24-41-00-861-002 .
(2) On the panel 50VU, release the ENG FADEC GND PWR/2 pushbutton switch.
Subtask 77-30-00-710-107-A
B. Test
(1) On the panel 50VU, push the ENG FADEC GND PWR 2 pushbutton switch and release it again.
NOTE: This action resets the FADEC memory.
(2) Adjust the brightness of the MCDU screen.
(3) Push the INIT mode key. The INIT page comes into view.
(4) Enter a new flight number.
(5) Start the engine 2 by the normal engine automatic start procedure Ref. AMM 71-00-00-710-043 or
the normal engine manual start procedure Ref. AMM 71-00-00-710-047 and let it become stable for 5
minutes.
NOTE: Operation of the engine for at least 3 minutes erases the LAST LEG REPORT related to the
last flight and the new fault is recorded in the EEC LAST LEG REPORT.
(6) Do a shutdown of the engine 2 by the discontinued start, restart and shutdown procedure Ref.
AMM 71-00-00-710-018 .
(7) Read the LAST LEG REPORT of the FADEC (2A and 2B) menu on the MCDU (Ref. 70-00-00 Page
Block 301 Task Supporting Data).
(a) Make a record of the maintenance message.
(b) Make a record of the channel FADEC 2A or FADEC 2B which found the fault.
(8) Fully decrease the brightness of the MCDU screen (display off).
4. Fault Isolation
(Ref. Fig. N2 Signal to EVMU (Engine 2) SHEET 1)
Subtask 77-30-00-810-085-A
A. If the test gives the maintenance message ENG2 PMA WINDING 4005EV:
· replace the PMA-EEC ( 4005EV ) , Ref. AMM 73-22-38-000-010 and Ref. AMM 73-22-38-400-010 .
(1) If the fault continues:
· replace the EVMU ( 2EV ) , Ref. AMM 77-32-34-000-041 and Ref. AMM 77-32-34-400-041 .
(2) If the fault continues:
· do a check and repair the wiring from the EVMU (2EV) to the engine dedicated alternator stator
(4005EV) : pins AB/8D, 7C to pins B/D, C Ref. ASM 77-32-02.
(3) If the fault continues:
· inspect the Engine Dedicated Alternator (EDA) Drive Gear Assembly Retention Nut Ref.
AMM 72-60-33-200-011 .
Subtask 77-30-00-710-108-A
B. Do the test given in Para. 3.
5. Close-up
Subtask 77-30-00-860-069-A
A. Put the aircraft back to its initial configuration.
(1) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
Ref. AMM 31-60-00-860-002 .
(2) On the panel 50VU, push the ENG FADEC GND PWR/2 pushbutton switch.
(3) De-energize the aircraft electrical circuits
Ref. AMM 24-41-00-862-002 . [Rev.6 from Feb 2017] 2026.04.04 04:37:52 UTC