Failure of the Thrust Reverser Hydraulic Control Unit on Engine 2
1. Possible Causes
· HCU-THRUST REV (4101KS)
· wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS).
· wiring from the EEC (4000KS) to the thrust reverser inhibition relay 2 (14KS2).
· wiring from the thrust reverser inhibition relay 2 (14KS2) to the thrust reverser HCU (4101KS)
· wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS)
· wiring from the EEC (4000KS) to the thrust reverser inhibition relay 2 (14KS2)
· EEC ( 4000KS )
· RELAY-THRUST REV INHIBITION, ENG 2 ( 14KS2 )
2 Job Set-up Information
A. Referenced Information
REFERENCE DESIGNATION
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 71-13-00-410-010 Closing of the Fan Cowls 437AL(447AL),438AR(448AR)
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 78-31-51-000-010 Removal of the Thrust Reverser Hydraulic Control Unit
Ref. AMM 78-31-51-400-010 Installation of the Thrust Reverser Hydraulic Control Unit
Thrust Reverser HCU - Engine 2, Channel A SHEET 1
Thrust Reverser HCU - Engine 2, Channel B SHEET 1
Figure 78(IAE)-30-00-991-01300-A / SHEET 1/1 - Thrust Reverser HCU - Engine 2, Channel A not
printed, as per printing preferences
Figure 78(IAE)-30-00-991-01400-A / SHEET 1/1 - Thrust Reverser HCU - Engine 2, Channel B not
printed, as per printing preferences
3. Fault Confirmation
Subtask 78-30-00-710-122-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 .
(a) Make a record of the FADEC 2A or 2B channel which found the fault.
4. Fault Isolation
(Ref. Fig. Thrust Reverser HCU - Engine 2, Channel A SHEET 1) (Ref. Fig. Thrust Reverser HCU - Engine 2,
Channel B SHEET 1)
Subtask 78-30-00-810-095-A
A. If the test gives the maintenance message HYD CONT UNIT/HC/EEC2:
· replace the HCU-THRUST REV (4101KS) Ref. AMM 78-31-51-000-010 and Ref.
AMM 78-31-51-400-010 .
(1) If the channel which found the fault is FADEC 2A and the fault continues:
· Do a check and repair the wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS). :
pins J1/C, k to pins A/7, 6
· Do a check and repair the wiring from the EEC (4000KS) to the thrust reverser inhibition relay 2
(14KS2). : pin J3/A to pin 2
· Do a check and repair the wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS). :
pin J3/B to pin A/5
· Do a check and repair the wiring from the thrust reverser inhibition relay 2 (14KS2) to the thrust
reverser HCU (4101KS) : pin A to pin A/4 Ref. ASM 73-25-16.
(2) If the channel which found the fault is FADEC 2B and the fault continues:
· do a check and repair the wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS) :
pins J7/C, k to pins B/7, 6
· do a check and repair the wiring from the EEC (4000KS) to the thrust reverser inhibition relay 2
(14KS2) : pin J9/A to pin 4
· do a check and repair the wiring from the EEC (4000KS) to the thrust reverser HCU (4101KS) : pin
J9/B to pin B/5
· do a check and repair the wiring from the thrust reverser inhibition relay 2 (14KS2) to the thrust
reverser HCU (4101KS) : pin B to pin B/4 Ref. ASM 73-25-16.
(3) If the fault continues:
· Replace the EEC ( 4000KS ) Ref. AMM 73-22-34-000-010 and Ref. AMM 73-22-34-400-010 .
(4) If the fault continues:
· Replace the RELAY-THRUST REV INHIBITION, ENG 2 ( 14KS2 ) .
Subtask 78-30-00-710-123-A
B. Do the test given in Para. 3.
5. Close-up
Subtask 78-30-00-860-077-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 .
(4) 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 04:38:08 UTC