Failure of the Thrust-Reverser Actuator Lock Indicator/Proximity Sensor on Engine 2, Channel B

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1. Possible Causes
· LOCK IND/PROX SENSOR-THRUST REV LOWER R ACTUATOR ( 4006KS )
· C/B-ENGINE/ENG2/OIL/QTY/AND REV SNSR/CHAN B ( 1EN2 )
· wiring from the lock indicator/proximity sensor (4006KS) to the EEC (4000KS)
· wiring from the lock indicator/proximity sensor (4006KS) to the C/B (1EN2)
· EEC ( 4000KS )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
Ref. AMM 71-13-00-410-010 Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
Ref. AMM 71-50-00-210-010 Wire Harness Visual Inspection - All Power Plant Electrical Cables
Ref. AMM 71-50-00-220-010 Wire Continuity Check - All Power Plant Electrical Cables
Ref. AMM 73-22-34-000-010 Removal of the Electronic Engine Control (EEC)
Ref. AMM 73-22-34-400-010 Installation of the Electronic Engine Control (EEC)
Ref. ASM 73-25-16
Ref. AMM 78-31-00-710-041 Operational Test of the Thrust Reverser System with the CFDS
Ref. AMM 78-31-15-000-010 Removal of the Lock Indicator Proximity Sensor
Ref. AMM 78-31-15-400-010 Installation of the Lock Indicator Proximity Sensor
REFERENCE DESIGNATION
Ref. AMM 78-32-00-410-010 Closing of the Thrust Reverser Halves
Right Thrust Reverser Lock Indicator/Proximity Sensor SHEET 1
Figure 78(IAE)-30-00-991-00200-A / SHEET 1/1 - Right Thrust Reverser Lock Indicator/Proximity
Sensor not printed, as per printing preferences
3. Fault Confirmation
Subtask 78-30-00-710-154-A
A. Test
(1) Do the operational test of the thrust reverser system with the CFDS (through FADEC 2A and 2B
menus) Ref. AMM 78-31-00-710-041 .
4. Fault Isolation
(Ref. Fig. Right Thrust Reverser Lock Indicator/Proximity Sensor SHEET 1)
Subtask 78-30-00-810-117-A
A. If the test gives the maintenance message REV SL SENS CHB/HC/EEC 2:
· examine the harness Ref. AMM 71-50-00-210-010 from the EEC (4000KS) to the right thrust-reverser
locking actuator Ref. ASM 73-25-16.
NOTE: IAE Service Bulletin V2500-ENG-71-0275 Revision 02 provides a re-routing procedure for Terminal
Module Assembly TM817, in order to decrease the probability of wiring damages and subsequent
faults caused by electrical issues. This Terminal Module Assembly is between the proximity
sensor and the C/B, and the oil quantity transmitter is directly plugged in it. Airbus recommends
the implementation of this Service Bulletin.
(1) If the fault continues:
· Replace the connector of the lock indicator/proximity sensor (4006KS).
(2) If the fault continues:
· Replace the LOCK IND/PROX SENSOR-THRUST REV LOWER R ACTUATOR ( 4006KS ) Ref.
AMM 78-31-15-000-010 and Ref. AMM 78-31-15-400-010 .
(3) If the fault continues:
· Replace the C/B-ENGINE/ENG2/OIL/QTY/AND REV SNSR/CHAN B ( 1EN2 ) .
(4) If the fault continues.
· Do a check of the wiring from the lock indicator/proximity sensor (4006KS) to the EEC (4000KS)
pins A/B, C to pins J7/k, s Ref. ASM 73-25-16 Ref. AMM 71-50-00-220-010 .
NOTE: While performing this task, it is recommended to thoroughly shake the wiring, in order to increase
the chances to isolate a potential defect that would cause intermittent electrical issues.
(a) If there is no continuity or there is intermittent electrical issue:
· Repair the above wiring.
(b) If there is continuity and there is no intermittent electrical issue:
· Do a check of the wiring from the lock indicator/proximity sensor (4006KS) to the C/B (1EN2)
pin A/A to pin 2 Ref. ASM 73-25-16 Ref. AMM 71-50-00-220-010 .
NOTE: While performing this task, it is recommended to thoroughly shake the wiring, in order to
increase the chances to isolate a potential defect that would cause intermittent electrical
issues.
(c) If there is no continuity or there is intermittent electrical issue:
· Repair the above wiring.
(d) If the fault continues, replace the wiring from the LOCK IND/PROX SENSOR-THRUST REV
LOWER R ACTUATOR ( 4006KS ) to the EEC ( 4000KS ) pins A/B, C to pin J7/k,s.
(e) If the fault continues, replace the wiring from the LOCK IND/PROX SENSOR-THRUST REV
LOWER R ACTUATOR ( 4006KS ) to the C/B-ENGINE/ENG2/OIL/QTY/AND REV SNSR/
CHAN B ( 1EN2 ) pin A/A to pin2.
(f) If there is continuity and there is no intermittent electrical issue:
· Replace the EEC ( 4000KS ) Ref. AMM 73-22-34-000-010 Ref. AMM 73-22-34-400-010 .
Subtask 78-30-00-710-155-A
B. Test
(1) Do the operational test of the thrust reverser system with the CFDS (through FADEC 2A and 2B
menus), then without the CFDS and engine running Ref. AMM 78-31-00-710-041 .
5. Close-up
Subtask 78-30-00-860-093-A
A. Put the aircraft back to its initial configuration.
(1) Make sure that the thrust reverser halves 461AL and 462AR are closed Ref.
AMM 78-32-00-410-010 .
(2) Make sure that the fan cowls 447AL and 448AR are closed Ref. AMM 71-13-00-410-010 . [Rev.6 from Feb 2017] 2026.04.04 04:38:09 UTC