Loss of the 26VAC Power Supply of the ADIRU 1

TASK 34-11-00-810-801-A
Loss of the 26VAC Power Supply of the ADIRU 1

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

3. Fault Confirmation
Subtask 34-11-00-865-050-A

A. Table of the circuit breakers used in this procedure:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	NAV PROBES/ADIRU 1/AND AOA 1/26VAC	5FP1	F07

Subtask 34-11-00-740-050-A

B. Test
(1) Do the Interface test of the ADR (system 1) AMM 34-13-00-740-002
(a) If you cannot close the circuit breaker (5FP1), go to Para. 4.A.(2).

4. Fault Isolation
Subtask 34-11-00-810-050-B

A. If the test gives the maintenance message AOA SENSOR1 (3FP1) SPLY :
(1) If the circuit breaker (5FP1) is closed:

(a) If there is 26VAC:

(b) If there is no 26VAC:

1 If there is no ground signal:

repair the wiring between ADIRU 1 pins AC/4,9 and the ground terminal ASM 341101.

2 If there is a ground signal:

do a check of the wiring between ADIRU 1 pins AC/10, 6 and the circuit breaker (5FP1) ASM 341101.

a If there is no continuity:

b If there is continuity:

(2) If the circuit breaker (5FP1) is open:

(a) If the circuit breaker trips:

1 If the fault continues:

do a check for a short to ground at the wiring between ADIRU 1 pins AC/10, 6 and the circuit breaker (5FP1) ASM 341101.

a If there is a short to ground:

b If there is no short to ground:

Subtask 34-11-00-740-051-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:32:13 UTC