Loss of the THS Monitor Transducer Signal for the SEC 2

TASK 27-94-00-810-840-A
Loss of the THS Monitor Transducer Signal for the SEC 2

1. Possible Causes

SEC-2 [1CE2]
Monitor Position Transducer
Command Position Transducer
wiring of the XDCR MON SPLY signal from the THS actuator (9CE) to the first terminal block
wiring of the XDCR MON V1, V2 signals from the THS actuator (9CE) to the SEC 2 (1CE2)
wiring of the XDCR COM SPLY signal from the THS actuator (9CE) to the first terminal block
wiring of the XDCR COM V1, V2 signals from the THS actuator (9CE) to the SEC 2 (1CE2)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 27-90-00-810-822-A	Loss of the ACS1 Signal of the SEC2 MON Side
TSM TASK 27-90-00-810-824-A	Loss of the ACS1 Signal of the ELAC2 MON Side and SEC2 MON Side
AMM 27-44-56-000-001	Removal of the Position Transducer from the THS Actuator
AMM 27-44-56-400-001	Installation of the Position Transducer to the THS Actuator
ASM 279413
AMM 27-94-34-000-001	Removal of the SEC
AMM 27-94-34-400-001	Installation of the SEC
AMM 27-96-00-710-022	Operational Test of the THS Actuator Electrical Control (Activation for BITE Test)
AMM 27-96-00-740-001	BITE Test of the EFCS (Ground Scanning)

3. Fault Confirmation
Subtask 27-94-00-700-096-A

A. Test
(1) Do the operational test of the THS actuator electrical control AMM 27-96-00-710-022.

NOTE: Do the ground setting only with the SEC 2.

(2) Do the BITE test of the EFCS (Ground Scanning) AMM 27-96-00-740-001.
(a) If the ground scanning gives the maintenance message:
SEC2 MON OR INPUT OF THS ACTR XDCR3 9CE

Refer to Para. Fault Isolation.

(b) If the ground scanning gives at least two maintenance messages of the list below:
SEC2 OR WIRING FROM L B ELEV MODE XDCR 34CE3
SEC2 OR WIRING FROM L ELEV POS MON XDCR
SEC2 OR WIRING FROM R B ELEV MODE XDCR 34CE4
SEC2 OR WIRING FROM R ELEV POS MON XDCR
SEC2 MON OR INPUT OF THS ACTR XDCR3 9CE

Do this trouble shooting procedure (Ref. TSM TASK 27-90-00-810-822).

(c) If the ground scanning gives at least two maintenance messages of the list below:
L B ELEV MODE XDCR 34CE3
L ELEV POS MON XDCR OF ELAC2/SEC2
R B ELEV MODE XDCR 34CE4
ELAC2 MON OR INPUT OF THS ACTR XDCR1 9CE
SEC2 MON OR INPUT OF THS ACTR XDCR3 9CE

Do this trouble shooting procedure (Ref. TSM TASK 27-90-00-810-824).

4. Fault Isolation
Subtask 27-94-00-810-089-A

A. If the BITE test gives the maintenance message:
SEC2 MON OR INPUT OF THS ACTR XDCR3 9CE

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 Monitor Position Transducer , AMM 27-44-56-000-001 and AMM 27-44-56-400-001.

(2) If the fault continues:

Replace the Command Position Transducer , AMM 27-44-56-000-001 and AMM 27-44-56-400-001.

(3) If the fault continues:

Do a check of the wiring of the XDCR MON SPLY signal from the THS actuator (9CE) to the first terminal block, ASM 279413.

(a) If there is no continuity, repair the wiring.
(b) If there is continuity:

Do a check and repair the wiring of the XDCR MON V1, V2 signals from the THS actuator (9CE) to the SEC 2 (1CE2), ASM 279413.

(4) If the fault continues:

Do a check of the wiring of the XDCR COM SPLY signal from the THS actuator (9CE) to the first terminal block, ASM 279413.

(a) If there is no continuity, repair the wiring.
(b) If there is continuity:

Do a check and repair the wiring of the XDCR COM V1, V2 signals from the THS actuator (9CE) to the SEC 2 (1CE2), ASM 279413.

Subtask 27-94-00-700-097-A

B. Do the tests given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:28:15 UTC