W DOC AIRBUS | TSM A320F

Loss of the DC Supply of the ADIRU3

TASK 34-14-00-810-901-A
Loss of the DC Supply of the ADIRU3

1. Possible Causes
  • ADIRU-3 [1FP3]
  • wiring between ADIRU3 pin AC/8 and the first terminal block
  • RELAY-ADIRS 3 PWR SHEDDING [14FP]
  • wiring of the ADIRS 3 PWR SHEDDING relay (14FP)
  • wiring from the relay (14FP) pins A2, X1 to the circuit breaker (6FP3)
  • C/B-ADIRS/ADIRU/3/28VDC [6FP3]
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
ASM 341101
AMM 34-12-34-000-001
Removal of the ADIRU
AMM 34-12-34-400-001
Installation of the ADIRU
AMM 34-14-00-740-004
SYSTEM TEST of the Inertial Reference (IR)
3. Fault Confirmation
Subtask 34-14-00-740-213-A
A. Test
Do the System test of the inertial reference (system 3) AMM 34-14-00-740-004.
4. Fault Isolation
Subtask 34-14-00-810-155-A
A. If the test gives the maintenance message ADIRU3 (1FP3) DC SUPPLY:
   (1) If there is no ground signal:
   (2) If there is a ground signal:
  • do a check for 28VDC at pin AC/7 of the rack connector.
     (a) If there is 28VDC:
  • install a new ADIRU3.
     (b) If there is no 28VDC:
  • replace the RELAY-ADIRS 3 PWR SHEDDING [14FP] .
       1 If the fault stops:
  • install the ADIRU3.
       2 If the fault continues:
  • do a check and repair the wiring of the ADIRS 3 PWR SHEDDING relay (14FP)
    . pin X2 to the ground point
    . pin A1 to the ADIRU 3 (1FP3) pin AC/7
    ASM 341101.
         a If the fault stops:
  • install the ADIRU 3.
         b If the fault continues:
  • do a check of the wiring from the relay (14FP) pins A2, X1 to the circuit breaker (6FP3)
    ASM 341101.

    . If there is no continuity:
    - repair the above wiring
    - install the ADIRU 3.
    . If there is continuity:
    - replace the C/B-ADIRS/ADIRU/3/28VDC [6FP3]
    - install the ADIRU 3.
Subtask 34-14-00-740-214-A
B. Do the test given in Para. 3.
[Rev.8 from Aug 2018] 2026.04.04 04:40:24 UTC
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