FDIMU Receives No Data from the ACARS-MU or ATSU

TASK 31-36-00-810-916-A
FDIMU Receives No Data from the ACARS-MU or ATSU

1. Possible Causes

wiring
ATSU [1TX1]
DMU/FDIU (FDIMU) [10TV]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-36-00-740-012	Test of the Flight Data Interface and Management Unit (FDIMU)
ASM 313605
AMM 31-36-34-000-002	Removal of the FDIU/DMU (FDIMU)
AMM 31-36-34-400-002	Installation of the FDIU/DMU (FDIMU)
AMM 46-21-00-710-001	Operational Test of the ATSU

3. Fault Confirmation
Subtask 31-36-00-740-204-B ** ON A/C NOT FOR ALL

A. Do the FDIMU (10TV) fault monitoring test (AIDS-part) AMM 31-36-00-740-012.

NOTE: Make sure that the circuit breakers 5TV, 5TX1 on the panel 121VU are closed during the test.

4. Fault Isolation
Subtask 31-36-00-810-130-B ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message:

ATSU (1TX1) / FDIMU (10TV)

(1) Do the operational test of the ATSU AMM 46-21-00-710-001.

(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 ATSU [1TX1] to the DMU/FDIU (FDIMU) [10TV] ASM 313605:

ATSU Connector AA/1E to FDIMU Connector AB/5J
ATSU Connector AA/1F to FDIMU Connector AB/5K
ATSU Connector AB/8A to FDIMU Connector AB/11J
ATSU Connector AB/8B to FDIMU Connector AB/11K

(3) If the fault continues:

replace the FDIMU (10TV) AMM 31-36-34-000-002 and AMM 31-36-34-400-002.

Subtask 31-36-00-740-205-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:30:07 UTC