Loss of the ELAC 1 MON BUS 1 Signal for the SEC 2 or the SEC 3

TASK 27-94-00-810-885-A
Loss of the ELAC 1 MON BUS 1 Signal for the SEC 2 or the SEC 3

1. Possible Causes

SEC-2 [1CE2]
SEC-3 [1CE3]
wiring of the DGI 11 signal from the SEC2 (1CE2) COM part and MON part to the first terminal block
wiring of the DGI 11 signal from the SEC3 (1CE3) COM part and MON part to the first terminal block.
wiring of the DSI 14 signal from the SEC2 (1CE2) COM part and MON part to the first terminal block
wiring of the DSI 14 signal from the SEC3 (1CE2) COM part and 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
ESPM 2052220
ASM 279249
ASM 279250
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 27-94-00-740-138-A

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

4. Fault Isolation
Subtask 27-94-00-810-122-A

A. If the test gives the maintenance message:
SEC2 OR BUS 1 FROM ELAC1 MON
Or
SEC3 OR BUS 1 FROM ELAC1 MON

replace the SEC-2 [1CE2] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

(1) If the fault continues:

replace the SEC-3 [1CE3] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

(2) 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 ELAC1 ASM 279250.

(3) If the fault continues:

at the ELAC1 receptacle, do a check of the insulation of the wiring of the DGO 01 signal ASM 279250 ESPM 2052220.

(4) If the fault continues:
(a) Do a check of the wiring of the DGI 11 signal from the SEC2 (1CE2) COM part and MON part to the first terminal block ASM 279250.

if there is continuity, see Para. (b)
if there is no continuity, repair the above wiring.

(b) Do a check of the wiring of the DGI 11 signal from the SEC3 (1CE3) COM part and MON part to the first terminal block. ASM 279250.

if there is continuity, see Para. (c)
if there is no continuity, repair the above wiring.

(c) Do a check of the wiring of the DSI 14 signal from the SEC2 (1CE2) COM part and MON part to the first terminal block ASM 279249.

if there is continuity, see Para. (d)
if there is no continuity, repair the above wiring .

(d) Do a check and repair the wiring of the DSI 14 signal from the SEC3 (1CE2) COM part and MON part to the first terminal block ASM 279249.

Subtask 27-94-00-740-139-A

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:28:19 UTC