Loss of the LGCIU 1 Output Bus by the DMC 3

TASK 31-63-00-810-922-A
Loss of the LGCIU 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

3. Fault Confirmation
Subtask 31-63-00-865-154-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	L/G/LGCIU/SYS1/NORM	1GA	C09
121VU	HYDRAULIC/LGCIU/SYS1/GRND SPLY	52GA	Q34

Subtask 31-63-00-740-254-A ** ON A/C NOT FOR ALL

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

Subtask 31-63-00-740-254-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 31-63-00-810-170-A ** ON A/C NOT FOR ALL

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

(1) If the fault continues:

do a check and repair the wiring from the DMC 3 (1WT3) pins AA/14D, 14E to the first terminal block ASM 316201.

Subtask 31-63-00-810-170-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message LGCIU1(5GA1)/DMC3(1WT3):

(1) If the fault continues:

do a check and repair the wiring from the DMC 3 (1WT3) pins AD/7J, 7K to the first terminal block ASM 316201.

Subtask 31-63-00-740-255-A

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

[Rev.8 from Aug 2018] 2026.04.04 04:30:46 UTC