Loss of the MDDU Interface with the CFDIU

TASK 31-38-00-810-818-A
Loss of the MDDU Interface with the CFDIU

1. Possible Causes

MDDU [1TD]
wiring

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 31-38-00-740-002	BITE Test of the Multipurpose Disk Drive Unit (MDDU)
ASM 313801
AMM 31-38-22-000-001	Removal of the MDDU
AMM 31-38-22-400-001	Installation of the MDDU

3. Fault Confirmation
Subtask 31-38-00-740-064-A ** ON A/C NOT FOR ALL

A. Do the BITE test of the Multipurpose Disk Drive Unit (MDDU) AMM 31-38-00-740-002.

4. Fault Isolation
Subtask 31-38-00-810-067-A ** ON A/C NOT FOR ALL

A. If the test gives the maintenance message CFDIU(1TW)/MDDU(1TD):

(1) Replace the MDDU [1TD] AMM 31-38-22-000-001 and AMM 31-38-22-400-001.
(2) If the fault continues:

do a check and repair the wiring from the MDDU (1TD) connector A/24, 25 to the first terminal block 1813VT ASM 313801.

Subtask 31-38-00-740-065-A ** ON A/C NOT FOR ALL

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

[Rev.8 from Aug 2018] 2026.04.04 04:30:10 UTC