W DOC AIRBUS | TSM A320F

EPSU - Communication Fault Message

TASK 33-51-00-810-806-A
EPSU - Communication Fault Message

1. Possible Causes
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 23-73-00-740-005
BITE-Test of the Cabin Intercommunication Data System (CIDS) through the CFDS
AMM 23-73-47-000-001
Removal of the Decoder/Encoder Unit B (300RH)
AMM 23-73-47-400-001
Installation of the Decoder/Encoder Unit B (300RH)
AMM 33-51-00-710-001
Operational Test of the Emergency Lights
AMM 33-51-00-710-006
Operational Test of Emergency Lights not with CIDS
ASM 335101
ASM 335102
AMM 33-51-38-000-001
Removal of the Emergency Power-Supply Unit (EPSU)
AMM 33-51-38-400-001
Installation of the Emergency Power-Supply Unit (EPSU)
3. Fault Confirmation
CAUTION: DO NOT USE THE TEACH-IN PROCEDURE AS AN ALTERNATIVE FOR TROUBLESHOOTING. A TEACH-IN PROCEDURE IS NOT A RESET PROCEDURE. BEFORE YOU DO A TEACH-IN PROCEDURE, MAKE SURE THAT YOU CORRECTED ALL FAILURES. IF YOU DO NOT OBEY THIS, FAILURES CAN CAUSE A MALFUNCTION OF THE CABIN EMERGENCY LIGHTING SYSTEM.
Subtask 33-51-00-710-060-A ** ON A/C NOT FOR ALL
A. Test
   (1) Do the BITE-test of the Cabin Intercommunication Data-System (CIDS) AMM 23-73-00-740-005.
   (2) Do the operational test of the emergency lighting system AMM 33-51-00-710-001.
4. Fault Isolation
Subtask 33-51-00-810-073-A ** ON A/C NOT FOR ALL
A. If the test gives a different maintenance message, do the trouble shooting procedure related to the maintenance message.
Subtask 33-51-00-810-055-C ** ON A/C NOT FOR ALL
B. If the operational test gives the maintenance message:
   (1) EPSU COMM FWD L:
     (a) If no LEDs come on or a red FAULT LED comes on:
     (b) If the green SYSTEM OK LED comes on:
  • do a check and repair the wiring between:
    POWER SUPPLY UNIT-EMERGENCY (10WL) pin X and DEU-B (300RH1) connector B/16,
    POWER SUPPLY UNIT-EMERGENCY (10WL) pin <P and DEU-B (300RH1) connector B/17 ASM 335101.
     (c) If the fault continues:
   (2) EPSU COMM EMER L:
     (a) If no LEDs come on or a red FAULT LED comes on:
     (b) If the green SYSTEM OK LED comes on:
  • do a check and repair the wiring between:
    POWER SUPPLY UNIT-EMERGENCY (11WL) pin X and DEU-B (300RH4) connector B/16,
    POWER SUPPLY UNIT-EMERGENCY (11WL) pin <P and DEU-B (300RH4) connector B/17 ASM 335102.
     (c) If the fault continues:
   (3) EPSU COMM EMER R:
     (a) If no LEDs come on or a red FAULT LED comes on:
     (b) If the green SYSTEM OK LED comes on:
  • do a check and repair the wiring between:
    POWER SUPPLY UNIT-EMERGENCY (12WL) pin X and DEU-B (300RH4) connector B/19,
    POWER SUPPLY UNIT-EMERGENCY (12WL) pin <P and DEU-B (300RH4) connector B/20 ASM 335102.
     (c) If the fault continues:
   (4) EPSU COMM AFT L:
     (a) If no LEDs come on or a red FAULT LED comes on:
     (b) If the green SYSTEM OK LED comes on:
  • do a check and repair the wiring between:
    POWER SUPPLY UNIT-EMERGENCY (13WL) pin X and DEU-B (300RH5) connector B/16,
    POWER SUPPLY UNIT-EMERGENCY (13WL) pin <P and DEU-B (300RH5) connector B/17 ASM 335102.
     (c) If the fault continues:
Subtask 33-51-00-710-061-A ** ON A/C NOT FOR ALL
C. Do the test as given in Para. 3.A.
5. Close-up
Subtask 33-51-00-860-069-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
[Rev.8 from Aug 2018] 2026.04.04 04:32:07 UTC
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