DOC AIRBUS | TSM A320FLoss of the Power Supply of the ACP 3 and AMU Card 3
TASK 23-51-00-810-820-A
Loss of the Power Supply of the ACP 3 and AMU Card 3
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 23-51-00-740-088-A 4. Fault Isolation
Subtask 23-51-00-865-055-A
[Rev.8 from Aug 2018]
2026.04.04 04:25:44 UTC
Loss of the Power Supply of the ACP 3 and AMU Card 3
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| AMM 23-51-00-740-002 | BITE Test of the Audio System |
| ASM 235104 | |
| AMM 23-51-12-000-001 | Removal of the Audio Control Panel (ACP) (2RN1, 2RN2, 2RN3, 2RN4, 2RN5) |
| AMM 23-51-12-400-001 | Installation of the Audio Control Panel (ACP) (2RN1, 2RN2, 2RN3, 2RN4, 2RN5) |
| AMM 23-51-34-000-001 | Removal of the Audio Management Unit (AMU) (1RN) |
| AMM 23-51-34-400-001 | Installation of the Audio Management Unit (AMU) (1RN) |
Subtask 23-51-00-740-088-A 4. Fault Isolation
Subtask 23-51-00-865-055-A
A. Table of the circuit breakers used in this procedure:
Subtask 23-51-00-810-069-B | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 121VU | COM NAV/ACP/THIRD/OCCPNT | 6RN | M02 |
B. If the BITE test gives the two maintenance messages ACP3(2RN3)/AMU(1RN) and AMU(1RN):
Subtask 23-51-00-740-089-A - Do a check of the circuit breaker C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] status.
- Replace the C/B C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] .
- Do a check and repair the wiring from the circuit breaker C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] to the first terminal block ASM 235104.
- Close it.
- Remove the ACP-3RD OCCPNT [2RN3] AMM 23-51-12-000-001
- Remove the AMU [1RN] AMM 23-51-34-000-001
- Close the circuit breaker C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] .
- Install the removed LRUs one by one until the circuit breaker C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] opens again:
. AMM 23-51-12-400-001 for the ACP-3RD OCCPNT [2RN3]
. AMM 23-51-34-000-001 for the AMU [1RN] . - Replace the faulty LRU.
- Replace the circuit breaker C/B-COM NAV/ACP/THIRD/OCCPNT [6RN] .
- Do a check and repair the wiring from:
. The ACP-3RD OCCPNT [2RN3] pin A/M to the first terminal block
. The AMU [1RN] pin AC/5 to the first terminal block ASM 235104. - Install the removed LRUs:
. AMM 23-51-12-400-001 for the ACP-3RD OCCPNT [2RN3]
. AMM 23-51-34-000-001 for the AMU [1RN] .
- Replace the ACP-3RD OCCPNT [2RN3] and the AMU [1RN] one by one until the fault is no longer there:
. AMM 23-51-12-000-001 and AMM 23-51-12-400-001 for the ACP-3RD OCCPNT [2RN3]
. AMM 23-51-34-000-001 and AMM 23-51-34-400-001 for the AMU [1RN] .
C. Do the test given in Para. 3.