Failure of the Right Blue Elevator-Servocontrol Position-Transducer

TASK 27-30-00-810-823-A
Failure of the Right Blue Elevator-Servocontrol Position-Transducer

1. Possible Causes

SERVO CTL-R ELEVATOR, OUTBD B [34CE4]
wiring of the POS XDCR COM SPLY signal from the servocontrol (34CE4) to the first terminal block
wiring of the POS XDCR COM V1, V2 signals from the servocontrol (34CE4) to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 27-90-00-810-819-A	Loss of the ACS1 Signal of the ELAC1 COM Side and SEC1 COM Side
TSM TASK 31-32-00-810-933-A	Failure of the Analog Links
AMM 27-34-00-040-001	Elevator Servocontrol Position-Transducer - Connection of the Spare Transducer
AMM 27-34-00-440-001	Reactivation of Elevator Servocontrol Position-Transducer
AMM 27-34-51-000-001	Removal of the Elevator Servo Control
AMM 27-34-51-400-001	Installation of the Elevator Servo Control
ASM 279307
ASM 279407
AMM 27-96-00-710-020	Operational Test of the Side Stick Assembly (Activation for the BITE Test)
AMM 27-96-00-740-001	BITE Test of the EFCS (Ground Scanning)

3. Fault Confirmation
Subtask 27-30-00-700-086-A

A. Test
(1) Do the operational test of the side stick assembly (Activation for the BITE test) AMM 27-96-00-710-020.
(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:
R B ELEV POS XDCR 34CE4 COM E1/S1 : USE STBY XDCR

refer to Para. Fault Isolation.

(b) If the ground scanning gives at least two maintenance messages of the list below:
L B ELEV POS XDCR 34CE3 COM E1/S1 : USE STBY XDCR
R B ELEV POS XDCR 34CE4 COM E1/S1 : USE STBY XDCR
THS ACTR XDCR2 9CE

do this trouble shooting procedure (Ref. TSM TASK 27-90-00-810-819).

4. Fault Isolation
Subtask 27-30-00-810-068-A

A. If the test gives the maintenance message:
R B ELEV POS XDCR 34CE4 COM E1/S1 : USE STBY XDCR
(1) Deactivate the defective RVDT and connect the spare RVDT AMM 27-34-00-040-001 and AMM 27-34-00-440-001.

NOTE: These AMM tasks are only applicable if the servocontrol has a spare RVDT (RVDT triplex or RVDT duplex).

(a) If the servocontrol has no spare RVDT (RVDT simplex), continue the procedure to the subsequent step (4.A.(2)).
(2) If the fault continues:

do the trouble shooting procedure (Ref. TSM TASK 31-32-00-810-933) related to the ANI 2-X analog input signal of the ELAC COM and SEC COM ASM 279307 and ASM 279407.

(3) If the fault continues:

replace the SERVO CTL-R ELEVATOR, OUTBD B [34CE4] AMM 27-34-51-000-001 and AMM 27-34-51-400-001.

NOTE: The resistance of primary and secondary windings must be between 30 ohms and 500 ohms.

(4) If the fault continues:
(a) Do a check of the wiring of the POS XDCR COM SPLY signal from the servocontrol (34CE4) to the first terminal block ASM 279307:

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

(b) Do a check and repair the wiring of the POS XDCR COM V1, V2 signals from the servocontrol (34CE4) to the first terminal block ASM 279307.

Subtask 27-30-00-700-087-A

B. Do the tests given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:27:32 UTC