W DOC AIRBUS | TSM A320F

Failure of the Captain Loud Speaker

TASK 31-53-00-810-922-A
Failure of the Captain Loud Speaker

1. Possible Causes
  • LOUD SPEAKER-CAPT [7WW]
  • FWC-1 [1WW1]
  • FWC-2 [1WW2]
  • wiring
  • C/B-CAPT/LOUD/SPKR [5WW]
  • MIXING BOX-AUDIO [15WW]
  • C/B-AUDIO MIXING [14WW]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
AMM 23-71-00-710-001
Operational Test of the CVR and the CVR Channel Recording
AMM 31-50-00-710-002
Operational Test of the Flight Warning Computer (FWC)
ASM 315101
ASM 315204
AMM 31-53-21-000-001
Removal of the Loudspeakers
AMM 31-53-21-400-001
Installation of the Loudspeakers
AMM 31-53-33-000-001
Removal of the Audio Mixing Box
AMM 31-53-33-400-001
Installation of the Audio Mixing Box
AMM 31-53-34-000-001
Removal of the Flight Warning Computer (FWC)
AMM 31-53-34-400-001
Installation of the Flight Warning Computer (FWC)
AMM 34-43-00-740-001
BITE Test of the TCAS
AMM 34-48-00-710-001
Operational Test of GPWS Ground Self-test Function
3. Fault Confirmation
Subtask 31-53-00-710-271-E
A. Test
   (1) Do the operational test of the Flight Warning Computer (FWC) AMM 31-50-00-710-002 if the fault causes inhibition of all the aural warnings.
   (2) Do the operational test of the CVR and the CVR channel recording AMM 23-71-00-710-001 only if the fault causes inhibition of the audio signal related to the CVR.
   (3) Do the operational test of GPWS ground self-test function AMM 34-48-00-710-001 only if the fault causes inhibition of the audio signal related to the GPWS.
   (4) Do the BITE test of the TCAS AMM 34-43-00-740-001 only if the fault causes inhibition of the audio signal related to the TCAS.
4. Fault Isolation
Subtask 31-53-00-865-067-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUCAPT/LOUD/SPKR5WWF10
** ON A/C NOT FOR ALL
121VUAUDIO MIXING14WWK03
Subtask 31-53-00-810-177-A ** ON A/C NOT FOR ALL
B. If the fault causes inhibition of all the aural warnings:
  • do a check of the status of the circuit breaker (5WW).
   (1) If the circuit breaker is closed:
  • do a check for 28VDC at pin A/A of the loud speaker (7WW) ASM 315101.
     (a) If there is 28VDC:
  • do a check for a ground signal at pins A/B and A/T of the loud speaker (7WW).
       1 If there is a ground signal:
         a If the fault continues:
       2 If there is no ground signal:
  • do a check and repair the wiring of pins A/B and A/T from the loud speaker (7WW) to the first terminal block ASM 315101.
     (b) If there is no 28VDC:
  • do a check for 28VDC at pin 2 of the circuit breaker (5WW) ASM 315101.
       1 If there is 28VDC:
  • do a check and repair the wiring from the circuit breaker (5WW) to the loud speaker (7WW) ASM 315101.
       2 If there is no 28VDC:
  • replace the C/B-CAPT/LOUD/SPKR [5WW] .
   (2) If the circuit breaker is open:
  • close the circuit breaker.
     (a) If the circuit breaker trips:
  • replace the C/B-CAPT/LOUD/SPKR [5WW] .
       1 If the circuit breaker trips again:
         a If the circuit breaker trips again:
  • do a check for a short to ground and repair the wiring from the circuit breaker (5WW) to the loud speaker (7WW) ASM 315101.
Subtask 31-53-00-810-178-B ** ON A/C NOT FOR ALL
C. If the fault only causes inhibition of the audio signal related to the CVR or TCAS:
   (1) If the fault continues:
  • do a check and repair the wiring of pins A/R and A/S from the loud speaker (7WW) to the first terminal block ASM 315204.
Subtask 31-53-00-810-177-B ** ON A/C NOT FOR ALL
D. If the fault causes inhibition of all the aural warnings:
  • do a check of the status of the circuit breaker (5WW).
  • do a check of the status of the circuit breaker (14WW).
   (1) if the circuit breaker (14WW) is closed:
  • do a check for 28VDC at pin A/L of the audio mixing box (15WW) ASM 315101:
     (a) if there is 28VDC:
     (b) if there is no 28VDC:
  • do a check for 28VDC at the circuit breaker (14WW):
       1 if there is 28VDC:
  • do a check and repair the wiring from the circuit breaker (14WW) to the audio mixing box (15WW).
       2 if there is no 28VDC:
  • replace C/B-AUDIO MIXING [14WW] .
   (2) if the circuit breaker (14WW) is open:
  • close the circuit breaker (14WW).
     (a) if the circuit breaker trips:
  • replace the C/B-AUDIO MIXING [14WW] .
       1 if the circuit breaker trips again
   (3) If the circuit breaker (5WW) is closed:
  • do a check for 28VDC at pin A/A of the loud speaker (7WW) ASM 315101.
     (a) If there is 28VDC:
  • do a check for a ground signal at pins A/B and A/T of the loud speaker (7WW).
       1 If there is a ground signal:
         a If the fault continues:
       2 If there is no ground signal:
  • do a check and repair the wiring of pins A/B and A/T from the loud speaker (7WW) to the first terminal block ASM 315101.
     (b) If there is no 28VDC:
  • do a check for 28VDC at pin 2 of the circuit breaker (5WW) ASM 315101.
       1 If there is 28VDC:
  • do a check and repair the wiring from the circuit breaker (5WW) to the loud speaker (7WW) ASM 315101.
       2 If there is no 28VDC:
  • replace the C/B-CAPT/LOUD/SPKR [5WW] .
   (4) If the circuit breaker is open:
  • close the circuit breaker.
     (a) If the circuit breaker trips:
  • replace the C/B-CAPT/LOUD/SPKR [5WW] .
       1 If the circuit breaker trips again:
         a If the circuit breaker trips again:
  • do a check for a short to ground and repair the wiring from the circuit breaker (5WW) to the loud speaker (7WW) ASM 315101.
Subtask 31-53-00-810-178-D ** ON A/C NOT FOR ALL
E. If the fault only causes inhibition of the audio signal related to the CVR or TCAS:
   (1) If the fault continues:
  • do a check and repair the wiring of pins A/R and A/S from the loud speaker (7WW) to the audio mixing box (15WW) pins J, K ASM 315204.
Subtask 31-53-00-810-179-A
F. If the fault only causes inhibition of the aural warnings related to the GPWS:
   (1) If the fault continues:
  • do a check and repair the wiring of pins A/K and A/L from the loud speaker (7WW) to the first terminal block ASM 315204.
Subtask 31-53-00-710-272-A
G. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:38:58 UTC
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