Loss of the LGCIU 1 Discrete on the DMC's

TASK 31-63-81-810-902-A
Loss of the LGCIU 1 Discrete on the DMC's

1. Possible Causes

LGCIU-1 [5GA1]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-60-00-740-007	GROUND SCANNING Test of the DMC
ASM 316200
AMM 32-31-71-000-001	Removal of the LGCIU
AMM 32-31-71-400-001	Installation of the LGCIU

3. Fault Confirmation
Subtask 31-63-81-740-250-A ** ON A/C NOT FOR ALL

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

4. Fault Isolation
Subtask 31-63-81-810-170-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance messages LGCIU1 FLIGHT DISCRETE (5GA1)/ DMC1(1WT1) and LGCIU1 FLIGHT DISCRETE (5GA1)/DMC2(1WT2) and LGCIU1 FLIGHT DISCRETE (5GA1)/DMC3(1WT3):

replace the LGCIU-1 [5GA1] AMM 32-31-71-000-001 and AMM 32-31-71-400-001

(1) if the fault continues:

check the wiring from LGCIU1(5GA1) pins AA/13K, 15K and pins AA/13J, 15J to the first terminal block ASM 316200

Subtask 31-63-81-740-251-A ** ON A/C NOT FOR ALL

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

[Rev.8 from Aug 2018] 2026.04.04 04:31:03 UTC