W DOC AIRBUS | TSM A320F

Failure of the Control of the Thrust-Reverser HCU Pressurizing-Valve through the two Channels on Engine 1

TASK 78-31-00-810-823-A
Failure of the Control of the Thrust-Reverser HCU Pressurizing-Valve through the two Channels on Engine 1

1. Possible Causes
  • HCU-THRUST REV (4101KS)
  • ECU [4000KS]
  • J5, J6 and thrust reverser harnesses
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 78-31-00-810-825-A
Failure of the Control of the Thrust-Reverser HCU Pressurizing-Valve through the Channel A on Engine 1
TSM TASK 78-31-00-810-826-A
Failure of the Control of the Thrust-Reverser HCU Pressurizing-Valve through the Channel B on Engine 1
AMM 71-50-00-210-001
Visual Inspection of the Power Plant Wire Harness
AMM 71-50-00-210-040
Visual Inspection of the Power Plant Wire Harnesses
AMM 71-51-43-000-049
Removal of the ECU (Channel A) to Thrust Reverser Junction Box Harnesses
AMM 71-51-43-400-049
Installation of the ECU (Channel A) to Thrust Reverser Junction Box Harnesses
AMM 71-51-44-000-002
Removal of the Thrust Reverser Harness 238W0908
AMM 71-51-44-400-002
Installation of the Thrust Reverser Harness 238W0908
AMM 73-21-60-000-001
Removal of the Electronic Control Unit (ECU)
AMM 73-21-60-400-001
Installation of the Electronic Control Unit (ECU)
AMM 78-31-00-710-040
Operational Test of the Thrust Reverser System
AMM 78-31-00-710-042
Operational Test of the Thrust Reverser System
AMM 78-31-51-000-040
Removal of the Hydraulic Control Unit
AMM 78-31-51-000-042
Removal of the Hydraulic Control Unit
AMM 78-31-51-400-040
Installation of the Hydraulic Control Unit
AMM 78-31-51-400-042
Installation of the Hydraulic Control Unit
3. Fault Confirmation
Subtask 78-31-00-710-114-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do the operational test of the thrust reverser system AMM 78-31-00-710-040.
Subtask 78-31-00-710-114-B ** ON A/C NOT FOR ALL
A. Test
   (1) Do the operational test of the thrust reverser system AMM 78-31-00-710-042.
4. Fault Isolation
Subtask 78-31-00-810-082-A ** ON A/C NOT FOR ALL
A. The fault messages are generated when the ECU detects an open circuit or a short to ground on both solenoids of the HCU pressurizing valve on channel A and channel B or on associated electrical wiring.
   (1) If the test gives the maintenance message PRESS VLV, J5, ECU then PRESS VLV, J6, ECU:
   (2) If the test does not give the maintenance message PRESS VLV, J5, ECU then PRESS VLV, J6, ECU: this indicates that the fault was intermittent and is no longer present:
  • do a check of the J5, J6 and thrust reverser harnesses and of the junction box for absence of damage AMM 71-50-00-210-040,
  • do a check of connectors for looseness, contamination, bent pins.
     (a) If damage is found:
     (b) If no damage is found:
  • no additional action is required.
   (3) If the maintenance message PRESS VLV, J5, ECU then PRESS VLV, J6, ECU becomes repetitive and is never confirmed during the operational test of the thrust reverser:
     (a) If the fault continues:
     (b) If the fault continues:
Subtask 78-31-00-810-082-B ** ON A/C NOT FOR ALL
A. The fault messages are generated when the ECU detects an open circuit or a short to ground on both solenoids of the HCU pressurizing valve on channel A and channel B or on associated electrical wiring.
   (1) If the test gives the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU:
   (2) If the test does not give the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU: this indicates that the fault was intermittent and is no longer present:
  • do a check of the J5, J6 and thrust reverser harnesses and of the junction box for absence of damage AMM 71-50-00-210-040,
  • do a check of connectors for looseness, contamination, bent pins.
     (a) If damage is found:
     (b) If no damage is found:
  • no additional action is required.
   (3) If the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU becomes repetitive and is never confirmed during the operational test of the thrust reverser:
     (a) If the fault continues:
     (b) If the fault continues:
Subtask 78-31-00-810-082-C ** ON A/C NOT FOR ALL
A. The fault messages are generated when the ECU detects an open circuit or a short to ground on both solenoids of the HCU pressurizing valve on channel A and channel B or on associated electrical wiring.
   (1) If the test gives the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU:
   (2) If the test does not give the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU: this indicates that the fault was intermittent and is no longer present:
  • do a check of the J5, J6 and thrust reverser harnesses and of the junction box for absence of damage AMM 71-50-00-210-001,
  • do a check of connectors for looseness, contamination, bent pins.
     (a) If damage is found:
     (b) If no damage is found:
  • no additional action is required.
   (3) If the maintenance message HCU (TRPV), J5, ECU then HCU (TRPV), J6, ECU becomes repetitive and is never confirmed during the operational test of the thrust reverser:
     (a) If the fault continues:
     (b) If the fault continues:
Subtask 78-31-00-710-115-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.
   (1) No additional maintenance action is required if the fault is not confirmed.
   (2) Repeat the fault isolation procedure if the fault continues.
[Rev.8 from Aug 2018] 2026.04.04 04:37:59 UTC
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