W DOC AIRBUS | TSM A320F

The PED Power supply is available during the operational test of the passenger emergency oxygen system

TASK 25-21-00-810-821-A
The PED Power supply is available during the operational test of the passenger emergency oxygen system

1. Possible Causes
  • aircraft wiring
  • Automatic Activation of the Oxygen System
  • Master Control Unit 55HP1
  • Master Control Unit 55HP2
  • relay 19WR
  • MASTER CONTROL UNIT - SEAT POWER SUPPLY [55HP1]
  • MASTER CONTROL UNIT - SEAT POWER SUPPLY [55HP2]
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
2
MULTIMETER - STANDARD
 B. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 35-23-00-810-801-A
Automatic System Activation Fault
TSM TASK 35-23-00-810-806-A
PAX Announcement Activation Fault
ASM 252100
AMM 25-21-00-710-002
Operational Test of the In-Seat Power-Supply System (PED Power Supply)
AMM 25-21-34-000-001
Removal of the Master Control Unit (MCU)
AMM 25-21-34-400-001
Installation of the Master Control Unit (MCU)
AMM 35-23-00-710-001
Operational Check of Manual Mask Release
3. Fault Confirmation
Subtask 25-21-00-710-070-A ** ON A/C NOT FOR ALL
A. Do the operational test of PED supply system AMM 25-21-00-710-002.
Subtask 25-21-00-710-070-E ** ON A/C NOT FOR ALL
A. Operational Test
   (1) Do the operational check of the manual mask release AMM 35-23-00-710-001.
   (2) Use a MULTIMETER - STANDARD to check if PED power at the outlet unit is available AMM 25-21-00-710-002.
4. Fault Isolation
Subtask 25-21-00-810-091-F ** ON A/C NOT FOR ALL
A. If the results of the operational test are unsatisfactory, do the procedure that follows:
NOTE: This aircraft has two MCUs (55HP1 and 55HP2). The procedure gives the troubleshooting of the MCU 55HP1. Do the procedure again to do the troubleshooting for the MCU 55HP2.
   (1) Disconnect the connector F from the MCU J6.
   (2) Use the MULTIMETER - STANDARD to do a check for continuity and for a short circuit in the aircraft wiring ASM 252100 between:
  • The MCU connector F and the diode module 1805VD pin 26. This is through:
    - The connector 2793VC pin 4
    - The connector 130VC pin 15.
     (a) If there is a fault in the aircraft wiring:
  • Repair and replace as necessary
  • Connect the connector F to the MCU connector J6
  • Do the test shown in Para. 3.
   (3) If there is no fault in the aircraft wiring, do the procedure that follows:
     (a) Do the troubleshooting for the Automatic Activation of the Oxygen System (Ref. TSM TASK 35-23-00-810-801).
     (b) If the fault continues, replace the Master Control Unit 55HP1 (and/or Master Control Unit 55HP2 ) AMM 25-21-34-000-001 and AMM 25-21-34-400-001.
Subtask 25-21-00-810-091-I ** ON A/C NOT FOR ALL
A. If the results of the operational test are unsatisfactory, do the procedure that follows:
   (1) At the related MCU (55HP1 and/or 55HP2):
     (a) Disconnect the connector F from the MCU J6
     (b) Use the MULTIMETER - STANDARD to do a check for continuity and for a short circuit in the aircraft wiring between ASM 252100:
  • The MCU connector F pin 35 and the diode module 1805VD pin 26. This is through:
    - The connector 2793VC pin 4.
     (c) If there is a fault in the aircraft wiring:
  • Repair and replace as necessary
  • Connect the connector F to the MCU connector J6
  • Do the test given in Para. 3.
   (2) If there is no fault in the aircraft wiring, do the procedure that follows:
     (a) Troubleshoot the relay 19WR (Ref. TSM TASK 35-23-00-810-806).
   (3) If there is no fault in the aircraft wiring, replace the related MASTER CONTROL UNIT - SEAT POWER SUPPLY [55HP1] and/or MASTER CONTROL UNIT - SEAT POWER SUPPLY [55HP2] ( AMM 25-21-34-000-001 and AMM 25-21-34-400-001).
Subtask 25-21-00-710-091-A ** ON A/C NOT FOR ALL
B. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:27:00 UTC
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