DOC AIRBUS | TSM A320FLoss of Yaw Damper and Rudder Trim and Rudder Travel Limitation Functions on the FAC 1
TASK 22-66-00-810-886-A
Loss of Yaw Damper and Rudder Trim and Rudder Travel Limitation Functions on the FAC 1
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
3. Fault Confirmation
Subtask 22-66-00-810-163-A
[Rev.8 from Aug 2018]
2026.04.04 04:25:23 UTC
Loss of Yaw Damper and Rudder Trim and Rudder Travel Limitation Functions on the FAC 1
1. Possible Causes
2. Job Set-up Information
A. Referenced Information
| REFERENCE | DESIGNATION |
|---|---|
| ASM 226501 | |
| AMM 22-66-34-000-002 | Removal of the FAC |
| AMM 22-66-34-400-002 | Installation of the FAC |
| AMM 22-96-00-710-001 | Operational Test of the AFS |
| AMM 24-41-00-861-002 | Energize the Aircraft Electrical Circuits from the External Power |
| AMM 29-10-00-863-003 | Pressurize the Blue Hydraulic System with a Hydraulic Ground Power-Cart |
| AMM 29-23-00-863-001 | Pressurize the Green Hydraulic System from the Yellow Hydraulic System through the PTU with the Electric Pump |
| AMM 29-24-00-863-001 | Pressurize the Yellow Hydraulic System with the Electric Pump |
WARNING:
MAKE SURE THAT ALL THE CIRCUITS IN MAINTENANCE ARE ISOLATED BEFORE YOU SUPPLY ELECTRICAL POWER TO THE AIRCRAFT.
WARNING:
MAKE SURE THAT THE TRAVEL RANGES OF THE FLIGHT CONTROL SURFACES ARE CLEAR BEFORE YOU PRESSURIZE/DEPRESSURIZE A HYDRAULIC SYSTEM.
Subtask 22-66-00-860-064-A A. Job Set-Up
(1) Aircraft Maintenance Configuration
(a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
(b) Pressurize the aircraft hydraulic systems
AMM 29-23-00-863-001, AMM 29-24-00-863-001 and AMM 29-10-00-863-003.
Subtask 22-66-00-865-092-A (1) Aircraft Maintenance Configuration
(a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
(b) Pressurize the aircraft hydraulic systems
AMM 29-23-00-863-001, AMM 29-24-00-863-001 and AMM 29-10-00-863-003.
B. Make sure that this(these) circuit breaker(s) is(are) closed:
Subtask 22-66-00-710-209-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 49VU | AUTO FLT/FAC1/28VDC | 5CC1 | B04 |
C. Test
(1) Open the circuit breaker 5CC1 for more than 5 seconds.
(2) After 10 seconds, close the circuit breaker 5CC1.
(3) After 2 minutes, do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FAC 1.
4. Fault Isolation(1) Open the circuit breaker 5CC1 for more than 5 seconds.
(2) After 10 seconds, close the circuit breaker 5CC1.
(3) After 2 minutes, do the operational test of the AFS AMM 22-96-00-710-001 and read the result for the FAC 1.
Subtask 22-66-00-810-163-A
A. If the test gives the maintenance message AFS: FAC1/P-B SW 12CC1:
(a) Replace the FAC-1 [1CC1] AMM 22-66-34-400-002
(2) If the resistance is not correct:
(a) Do a check of the wiring between:
1 If there is no continuity:
Subtask 22-66-00-710-210-A - Open the circuit breaker 5CC1
- Remove the FAC-1 AMM 22-66-34-000-002
- Do a check of the resistance between the pins AB/13G and AB/2G of the FAC-1 rack connector
- Do a check of the resistance between the pins AE/13G and AE/2G of the FAC-1 rack connector
NOTE: The resistance must be lower than 10 Ohms.
(1) If the resistance is correct: (a) Replace the FAC-1 [1CC1] AMM 22-66-34-400-002
(2) If the resistance is not correct:
(a) Do a check of the wiring between:
- The pin AB/13G of the FAC-1 (1CC1) and the pin A/D3 of the FLT CTL/FAC pushbutton switch (12CC1)
- The pin A/D1 of the FLT CTL/FAC pushbutton switch (12CC1) and the pin AB/2G of the FAC-1 (1CC1).
- The pin AE/13G of the FAC-1 (1CC1) and the pin A/C3 of the FLT CTL/FAC pushbutton switch (12CC1)
- The pin A/C1 of the FLT CTL/FAC pushbutton switch (12CC1) and the pin AE/2G of the FAC-1 (1CC1)
1 If there is no continuity:
- Repair the above wiring.
- Replace the P/BSW-FLT CTL/FAC1 [12CC1] .
- Install the above removed FAC-1 AMM 22-66-34-400-002.
B. Do the test given in Para. 3.