Failure of the Left Green Elevator-Servocontrol Mode-Transducer

TASK 27-30-00-810-820-A
Failure of the Left Green Elevator-Servocontrol Mode-Transducer

1. Possible Causes

SERVO CTL-L ELEVATOR, INBD G [34CE1]
wiring of the MODE XDCR SPLY signal from the servocontrol (34CE1) to the first terminal block
wiring of the MODE XDCR V1 signal from the servocontrol (34CE1) to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 27-90-00-810-820-A	Loss of the ACS1 Signal of the ELAC1 MON Side and SEC1 MON Side
TSM TASK 31-32-00-810-933-A	Failure of the Analog Links
AMM 27-34-51-000-006	Removal of the Elevator Servo Control Actuator Mode Selector Valve Transducer MSVT
AMM 27-34-51-400-005	Installation of the Elevator Servo Control Actuator Mode Selector Valve Transducer MSVT
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 27-30-00-700-080-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:
L G ELEV MODE XDCR 34CE1

refer to Para. Fault Isolation.

(b) If the ground scanning gives at least two maintenance messages of the list below:
L ELEV POS MON XDCR OF ELAC1/SEC1
L G ELEV MODE XDCR 34CE1
R B ELEV POS MON XDCR OF ELAC1/SEC1
R Y ELEV MODE XDCR 34CE2
THS ACTR XDCR2 MON 9CE

do this trouble shooting procedure (Ref. TSM TASK 27-90-00-810-820).

4. Fault Isolation
Subtask 27-30-00-810-065-A

A. If the test gives the maintenance message:
L G ELEV MODE XDCR 34CE1

do the trouble shooting procedure (Ref. TSM TASK 31-32-00-810-933) related to the ANI 7-X analog input signal of the ELAC MON and SEC MON ASM 279307 and ASM 279407.

(1) If the fault continues:

replace the SERVO CTL-L ELEVATOR, INBD G [34CE1] AMM 27-34-51-000-006 and AMM 27-34-51-400-005.

NOTE: The resistance of the primary winding of the elevator servocontrol mode-transducer (pins C/K and C/L) must be 96 ohms +/- 10 ohms, and the resistance of the secondary winding of the elevator servocontrol mode-transducer (pins (C/U and C/J) must be 700 ohms +/- 70 ohms. The insulation must be more than 10 Mohms.
These values are given for information only. You can use these values to do a check of the component electrical part of the wiring before you replace the component. But by this procedure, the check of the component mechanical part is not done.
For primary winding (power supply):

If you do the resistance check from the avionics compartment, you must disconnect the transducer of the Right Yellow Elevator Servo Control.

(2) If the fault continues:
(a) Do a check of the wiring of the MODE XDCR SPLY signal from the servocontrol (34CE1) to the first terminal block ASM 279307:

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

(b) Repair the wiring of the MODE XDCR V1 signal from the servocontrol (34CE1) to the first terminal block ASM 279307.

Subtask 27-30-00-700-081-A

B. Do the tests given in Para. 3.

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