Loss of the BUS 1 Signal for the SEC 1

TASK 27-94-00-810-876-A
Loss of the BUS 1 Signal for the SEC 1

1. Possible Causes

SEC-1 [1CE1]
wiring of the DGO 01 signal from the SEC 1 (1CE1) COM part to the first terminal block
wiring of the DGO 01 signal from the SEC 1 (1CE1) MON part to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 31-32-00-810-934-A	Failure of the Digital Links
ASM 279253
AMM 27-94-34-000-001	Removal of the SEC
AMM 27-94-34-400-001	Installation of the SEC
AMM 27-96-00-740-001	BITE Test of the EFCS (Ground Scanning)

3. Fault Confirmation
Subtask 27-94-00-740-120-A

A. Test
(1) Do the BITE test of the EFCS (ground scanning) AMM 27-96-00-740-001.

4. Fault Isolation
Subtask 27-94-00-810-113-A

A. If the BITE test gives the maintenance message:
SEC1 COM BUS1
or
SEC1 MON BUS1

(1) If the fault continues:

do the trouble shooting procedure (Ref. TSM TASK 31-32-00-810-934) related to the DGO 01 digital output signal of the SEC 1 ASM 279253.

(2) If the fault continues:

do a check and repair the wiring of the DGO 01 signal from the SEC 1 (1CE1) COM part to the first terminal block if the maintenance message is SEC 1 COM BUS 1 ASM 279253
or
do a check and repair the wiring of the DGO 01 signal from the SEC 1 (1CE1) MON part to the first terminal block if the maintenance message is SEC 1 MOM BUS 1 ASM 279253.

Subtask 27-94-00-740-121-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:28:18 UTC