Loss of the IRS 1 Output Bus by the DMC 3

TASK 31-63-00-810-863-A
Loss of the IRS 1 Output Bus by the DMC 3

1. Possible Causes

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-60-00-740-002	Perform Electronic Instrument System (EIS) Input Test
AMM 31-60-00-740-007	GROUND SCANNING Test of the DMC
ASM 316201
AMM 31-63-34-000-001	Removal of the DMC
AMM 31-63-34-400-001	Installation of the DMC
AMM 34-12-34-000-001	Removal of the ADIRU
AMM 34-12-34-400-001	Installation of the ADIRU

3. Fault Confirmation
Subtask 31-63-00-865-095-A

A. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	NAV PROBES/ADIRU 1/AND AOA 1/26VAC	5FP1	F07
49VU	NAV PROBES/ADIRU1/115VAC	4FP1	F06
105VU	ADIRS/ADIRU1/28VDC	6FP1	C02

Subtask 31-63-00-740-136-A ** ON A/C NOT FOR ALL

B. Test
Do the EIS input test AMM 31-60-00-740-002.

Subtask 31-63-00-740-136-B ** ON A/C NOT FOR ALL

B. Test
Do the Ground Scanning Test of the DMC AMM 31-60-00-740-007.

4. Fault Isolation
Subtask 31-63-00-810-111-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message DMC 3 : NO IRS 1 DATA:

(1) If the fault continues:

do a check and repair the wiring from the DMC 3 (1WT3) pins AA/5C, 5D to the first terminal block ASM 316201.

Subtask 31-63-00-810-111-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message ADIRU1(1FP1) BUS3 IR / DMC3(1WT3)

(1) If the fault continues:

do a check and repair the wiring from the ADIRU1 (1FP1) pins AB-10C/11C to the DMC3 (1WT3) pins AA-4C/4D ASM 316201.

(2) If the fault continues:

Subtask 31-63-00-740-137-A

B. Do the test given in Para. 3.B.

[Rev.8 from Aug 2018] 2026.04.04 04:30:42 UTC