DOC AIRBUS | TSM A320FLoss of the Altitude Bus 1 of the RA Transceiver 1 Identified by the EFCS1 or the EFCS2
TASK 34-42-00-810-803-A
Loss of the Altitude Bus 1 of the RA Transceiver 1 Identified by the EFCS1 or the EFCS2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 34-42-00-865-052-A
Subtask 34-42-00-810-054-A
[Rev.8 from Aug 2018]
2026.04.04 04:33:07 UTC
Loss of the Altitude Bus 1 of the RA Transceiver 1 Identified by the EFCS1 or the EFCS2
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| ESPM 2053230 | |
| AMM 27-96-00-740-001 | BITE Test of the EFCS (Ground Scanning) |
| ASM 344201 | |
| AMM 34-42-11-000-001 | Removal of the Radio Altimeter Antenna |
| AMM 34-42-11-400-001 | Installation of the Radio Altimeter Antenna |
| AMM 34-42-33-000-001 | Removal of the Radio Altimeter Transceiver |
| AMM 34-42-33-400-001 | Installation of the Radio Altimeter Transceiver |
Subtask 34-42-00-865-052-A
A. Make sure that this(these) circuit breaker(s) is(are) closed:
Subtask 34-42-00-740-054-A 4. Fault Isolation| PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 121VU | COM NAV/RAD ALTM/1 | 1SA1 | K11 |
Subtask 34-42-00-810-054-A
A. If the test gives the maintenance message RA1:
Subtask 34-42-00-740-055-A - replace the XCVR-RA, 1 [2SA1] AMM 34-42-33-000-001 and AMM 34-42-33-400-001.
- do a check and repair the wiring of the ALTITUDE BUS 1 from the XCVR-RA, 1 [2SA1] to the first terminal block ASM 344201.
- replace the ANTENNA-RA RCPTN, 1 [5SA1] and ANTENNA-RA XMSN, 1 [6SA1] AMM 34-42-11-000-001 and AMM 34-42-11-400-001.
- do a check and replace if necessary the coaxial cable from the XCVR-RA, 1 [2SA1] pin AA/C to the ANTENNA-RA RCPTN, 1 [5SA1] ASM 344201 ESPM 2053230.
- do a check and replace if necessary the coaxial cable from the XCVR-RA, 1 [2SA1] pin AB/C to the ANTENNA-RA XMSN, 1 [6SA1] ASM 344201 ESPM 2053230.
B. Do the test given in Para. 3.