DOC AIRBUS | TSM A320FPHMU Internal Failure
TASK 77-31-00-810-801-A
PHMU Internal Failure
1. Possible Causes
A. Referenced Information
3. Fault Isolation
Subtask 77-31-00-860-050-A ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:37:57 UTC
PHMU Internal Failure
1. Possible Causes
- PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS]
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 77-31-01-000-801 | Removal of the Prognostics and Health Management Unit (PHMU) |
| AMM 77-31-01-400-801 | Installation of the Prognostics and Health Management Unit (PHMU) |
| AMM 78-36-00-010-802 | Opening of the Thrust Reverser Cowl-Doors |
| AMM 78-36-00-410-802 | Closing of the Thrust Reverser Cowl-Doors |
EEC and PHMU Wiring HarnessesWARNING:
BE CAREFUL WHEN YOU DO WORK ON THE ENGINE AFTER SHUTDOWN. THE ENGINE CAN STAY HOT FOR A LONG TIME. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
WARNING:
REFER TO THE MSDS FOR ALL MATERIAL USED AND THE MANUFACTURER'S SAFETY INSTRUCTIONS FOR ALL EQUIPMENT USED. IF YOU DO NOT OBEY THIS WARNING, INJURY CAN OCCUR.
CAUTION:
MAKE SURE YOU REMOVE ELECTRICAL POWER FROM THE EEC BEFORE YOU REMOVE THE ELECTRICAL CONNECTORS. IF YOU DO NOT OBEY THIS INSTRUCTION, DAMAGE TO THE EEC CAN OCCUR.
Subtask 77-31-00-810-050-A ** ON A/C NOT FOR ALL A. If maintenance message ENG1D0677PHMU INTERNAL FAIL or ENG2D0677PHMU INTERNAL FAIL does not come back:
(1) Examine the harnesses and electrical connectors as described in the Component And Harness Intermittent Fault Isolation Procedure.
(a) If you find no damage:
1 Return the engine to service. Monitor the engine for reoccurring maintenance message.
(2) If the maintenance message ENG1D0677PHMU INTERNAL FAIL or ENG2D0677PHMU INTERNAL FAIL comes back (hard fault) in channel A or channel B, perform troubleshooting in the next step.
(a) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(3) Replace PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS] AMM 77-31-01-000-801 and AMM 77-31-01-400-801.
(a) Do the test given in Para. 3.
4. Close-up(1) Examine the harnesses and electrical connectors as described in the Component And Harness Intermittent Fault Isolation Procedure.
(a) If you find no damage:
1 Return the engine to service. Monitor the engine for reoccurring maintenance message.
(2) If the maintenance message ENG1D0677PHMU INTERNAL FAIL or ENG2D0677PHMU INTERNAL FAIL comes back (hard fault) in channel A or channel B, perform troubleshooting in the next step.
(a) Open the thrust reverser cowl-doors AMM 78-36-00-010-802.
(3) Replace PROGNOSTICS AND HEALTH MANAGEMENT UNIT [4609KS] AMM 77-31-01-000-801 and AMM 77-31-01-400-801.
(a) Do the test given in Para. 3.
Subtask 77-31-00-860-050-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close the thrust reverser cowl-doors AMM 78-36-00-410-802.