W DOC AIRBUS | TSM A320F

Reading Light - Fault in the Power Supply to the Reading Lights

TASK 33-25-00-810-803-A
Reading Light - Fault in the Power Supply to the Reading Lights

1. Possible Causes
  • READING-LIGHT POWER UNIT
  • wiring
  • RELAY 7LW
  • RELAY 8LW
  • DEU-A
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
ASM 237313
AMM 23-73-38-000-001
Removal of the Power Unit for the Passenger Reading Light
AMM 23-73-38-400-001
Installation of the Power Unit for the Passenger Reading Light
AMM 23-73-46-000-001
Removal of the Decoder/Encoder Unit A (200RH)
AMM 23-73-46-400-001
Installation of the Decoder/Encoder Unit A (200RH)
AMM 33-25-00-710-001
Operational Test of the Passenger Reading Light System
ASM 332501
AMM 33-27-00-740-001
Bite Test of the Cabin Attendant Work-Light through MCDU
3. Fault Confirmation
Subtask 33-25-00-710-052-A ** ON A/C NOT FOR ALL
A. Do the BITE test of the passenger reading lights with the MCDU AMM 33-27-00-740-001.
Subtask 33-25-00-710-058-A ** ON A/C NOT FOR ALL
B. Do the operational test of the passenger reading-light system AMM 33-25-00-710-001.
4. Fault Isolation
Subtask 33-25-00-810-062-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 33-25-00-810-052-A ** ON A/C NOT FOR ALL
B. If the operational test gives the maintenance message POWER PCB XX R (XX seat row) and all reading lights on one right side PSIU do not come on:
  • do a check for 115 VAC at the related READING-LIGHT POWER UNIT connector A/A ASM 237313.
   (1) If there is approx. 115 VAC:
   (2) If there is no 115 VAC:
  • do a check and repair the wiring between the related:
    READING-LIGHT POWER UNIT conn. A/A and RELAY 7LW conn. A2,
    READING-LIGHT POWER UNIT conn. A/A and RELAY 7LW conn. B2,
    READING-LIGHT POWER UNIT conn. A/A and RELAY 7LW conn. C2,
    READING-LIGHT POWER UNIT conn. A/B and GND ASM 237313 and ASM 332501.
Subtask 33-25-00-810-057-A ** ON A/C NOT FOR ALL
C. If the operational test gives the maintenance message POWER PCB XX L (XX seat row) and all reading lights on one left side PSIU do not come on:
  • do a check for 115 VAC at the related READING-LIGHT POWER UNIT connector A/A ASM 237313.
   (1) If there is approx. 115 VAC:
   (2) If there is no 115 VAC:
  • do a check and repair the wiring between the related:
    READING-LIGHT POWER UNIT conn. A/A and RELAY 8LW conn. A2,
    READING-LIGHT POWER UNIT conn. A/A and RELAY 8LW conn. B2,
    READING-LIGHT POWER UNIT conn. A/A and RELAY 8LW conn. C2,
    READING-LIGHT POWER UNIT conn. A/B and GND ASM 237313 and ASM 332501.
Subtask 33-25-00-810-058-A ** ON A/C NOT FOR ALL
D. If the operational test gives two or more maintenance messages POWER PCB XX R (XX seat row) and all reading lights in two or more right side PSIUs in series do not come on:
  • do a check of the RELAY 7LW and replace it if necessary.
   (1) If the fault continues:
  • do a check and repair the wiring between the:
    CB 1LW and RELAY 7LW conn. A1,
    CB 2LW and RELAY 7LW conn. B1,
    CB 3LW and RELAY 7LW conn. C1,
    RELAY 7LW conn. A2 and READING-LIGHT POWER UNIT conn. D,
    RELAY 7LW conn. B2 and READING-LIGHT POWER UNIT conn. D,
    RELAY 7LW conn. C2 and READING-LIGHT POWER UNIT conn. D ASM 237313 and ASM 332501.
Subtask 33-25-00-810-059-A ** ON A/C NOT FOR ALL
E. If the operational test gives two or more maintenance messages POWER PCB XX L (XX seat row) and all reading lights in two or more left side PSIUs in series do not come on:
  • do a check of the RELAY 8LW and replace it if necessary.
   (1) If the fault continues:
  • do a check and repair the wiring between the:
    CB 4LW and RELAY 8LW conn. A1,
    CB 5LW and RELAY 8LW conn. B1,
    CB 6LW and RELAY 8LW conn. C1,
    RELAY 8LW conn. A2 and READING-LIGHT POWER UNIT conn. D,
    RELAY 8LW conn. B2 and READING-LIGHT POWER UNIT conn. D,
    RELAY 8LW conn. C2 and READING-LIGHT POWER UNIT conn. D ASM 237313 and ASM 332501.
Subtask 33-25-00-810-060-A ** ON A/C NOT FOR ALL
F. If the operational test gives the maintenance message POWER PCB XX L, R and all reading lights come on:
Subtask 33-25-00-710-054-A ** ON A/C NOT FOR ALL
G. Do the test given in Para. 3.A.
5. Close-up
Subtask 33-25-00-860-051-A ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
[Rev.8 from Aug 2018] 2026.04.04 04:31:55 UTC
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