DMU Receives No Data from the LGCIU 1 or LGCIU 2

TASK 31-36-00-810-818-A
DMU Receives No Data from the LGCIU 1 or LGCIU 2

1. Possible Causes

wiring
LGCIU-1 [5GA1]
LGCIU-2 [5GA2]
DMU [1TV]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-36-00-710-001	Test of the DMU
AMM 31-36-34-000-001	Removal of the Data Management Unit (DMU)
AMM 31-36-34-400-001	Installation of the Data Management Unit (DMU)
ASM 313701
AMM 32-69-00-740-001	BITE Check of Landing-Gear Control Interface-Unit (LGCIU) With Use of MCDU to Ensure that Continuous BITE is Operative

3. Fault Confirmation
Subtask 31-36-00-740-062-A ** ON A/C NOT FOR ALL

A. Do the DMU (1TV) fault monitoring test AMM 31-36-00-710-001.

NOTE: Make sure that the circuit breakers 1TV, 2GA, 52GA on the panel 121VU and 1GA on the panel 49VU are closed during the test.

4. Fault Isolation
Subtask 31-36-00-810-058-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message:

NO LGCIU 1 DATA, or
NO LGCIU 2 DATA

(1) Do the BITE Test of the Landing Gear AMM 32-69-00-740-001.

(a) If the test gives a different maintenance message, you can find the related trouble shooting procedure in the applicable Page Block 201.

(2) If the fault continues:

do a check and repair the wiring from the LGCIU-1 [5GA1] or LGCIU-2 [5GA2] to the DMU [1TV] ASM 313701:

LGCIU 1 Connector AA/13K to DMU Connector AA/1C
LGCIU 1 Connector AA/15K to DMU Connector AA/1D
or,
LGCIU 2 Connector AA/13K to DMU Connector AB/1C
LGCIU 2 Connector AA/15K to DMU Connector AB/1D

(3) If the fault continues:

replace the DMU (1TV) AMM 31-36-34-000-001 and AMM 31-36-34-400-001.

Subtask 31-36-00-740-063-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:30:02 UTC