W DOC AIRBUS | TSM A320F

Loss of FAC 1

TASK 22-66-00-810-890-A
Loss of FAC 1

1. Possible Causes
  • 28VDC FAC1 Power Supply wiring
  • SERVO ACTR-YAW DAMPER, 1 [3CC1]
  • FAC-1 [1CC1]
  • RELAY-RTL SYS1 [13CC1]
  • RELAY-RUD TRIM 1 [7CC1]
  • ACTUATOR-RUDDER TRIM [10CC]
  • LIMITATION UNIT-RUDDER TRAVEL [4CC]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
TSM TASK 22-63-00-810-801-A
Loss of the Yaw Damper Function on the FAC 1
AMM 22-66-34-000-002
Removal of the FAC
AMM 22-66-34-400-002
Installation of the FAC
ASM 226701
AMM 22-96-00-710-001
Operational Test of the AFS
AMM 27-22-51-000-001
Removal of the Rudder Trim Actuator
AMM 27-22-51-400-001
Installation of the Rudder Trim Actuator
AMM 27-23-51-000-001
Removal of the Rudder Travel Limitation Unit
AMM 27-23-51-400-001
Installation of the Rudder Travel-Limitation Unit
3. Fault Confirmation
CAUTION: DO NOT SWAP FLIGHT AUGMENTATION COMPUTERS. IF THERE IS A SHORT CIRCUIT, YOU WILL CAUSE DAMAGE TO A SERVICEABLE COMPUTER WHEN YOU SWAP THEM.
Subtask 22-66-00-710-216-A
A. Not applicable.
4. Fault Isolation
Subtask 22-66-00-865-095-A
A. Table of the circuit breakers used in this procedure:
PANELDESIGNATIONFINLOCATION
** ON A/C ALL
49VUAUTO FLT/FAC1/28VDC5CC1B04
Subtask 22-66-00-810-168-A ** ON A/C NOT FOR ALL
B. If the fault symptom is identified by the trip of the 28VDC FAC1 circuit breaker:
  • do a check for short circuit of the 28VDC FAC1 Power Supply wiring between:
    . the pin 2 of the AUTO FLT/FAC1 circuit breaker (5CC1) and respectively:
    .. the pin AC/2 of the FAC1 (1CC1)
    .. the pin A/A2 of the RTL SYS 1 relay (13CC1)
    .. the pin A/A2 of the RUD TRIM 1 relay (7CC1)
    . the pin A/A1 of the RTL SYS 1 relay (13CC1) and the pin A/A of the RUDDER TRAVEL limitation unit (4CC)
    . the pin A/A1 of the RUD TRIM 1 relay (7CC1) and the pin B/T of the RUDDER TRIM actuator (10CC)
    ASM 226701.
   (1) If the wiring is not correct:
  • repair it.
   (2) If the fault continues:
NOTE: Disregard the maintenance message.
   (3) If the fault continues:
  • replace the RELAY-RTL SYS1 [13CC1] and the RELAY-RUD TRIM 1 [7CC1] .
   (4) If the fault continues:
   (5) If the fault continues:
   (6) If the fault continues:
Subtask 22-66-00-810-168-B ** ON A/C NOT FOR ALL
B. If the fault symptom is identified by the trip of the 28VDC FAC1 circuit breaker:
  • do a check for short circuit of the 28VDC FAC1 Power Supply wiring between:
    . the pin 2 of the AUTO FLT/FAC1 circuit breaker (5CC1) and respectively:
    .. the pin AC/7 of the FAC1 (1CC1)
    .. the pin A/A2 of the RTL SYS 1 relay (13CC1)
    .. the pin A/A2 of the RUD TRIM 1 relay (7CC1)
    . the pin A/A1 of the RTL SYS 1 relay (13CC1) and the pin A/A of the RUDDER TRAVEL limitation unit (4CC)
    . the pin A/A1 of the RUD TRIM 1 relay (7CC1) and the pin B/T of the RUDDER TRIM actuator (10CC)
    ASM 226701.
   (1) If the wiring is not correct:
  • repair it.
   (2) If the fault continues:
NOTE: Disregard the maintenance message.
   (3) If the fault continues:
  • replace the RELAY-RTL SYS1 [13CC1] and the RELAY-RUD TRIM 1 [7CC1] .
   (4) If the fault continues:
   (5) If the fault continues:
   (6) If the fault continues:
Subtask 22-66-00-810-177-A
C. If the fault symptom is not identified by the trip of the 28VDC FAC1 circuit breaker:
NOTE: Disregard the maintenance message.
   (1) If the fault continues:
  • replace the RELAY-RTL SYS1 [13CC1] and the RELAY-RUD TRIM 1 [7CC1] .
   (2) If the fault continues:
   (3) If the fault continues:
   (4) If the fault continues:
Subtask 22-66-00-710-219-A
D. Do the Operational Test of the AFS AMM 22-96-00-710-001.
[Rev.8 from Aug 2018] 2026.04.04 04:25:24 UTC
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