Failure of the THS Actuator Servo Motor 2 for the ELAC 1

TASK 27-93-00-810-845-A
Failure of the THS Actuator Servo Motor 2 for the ELAC 1

1. Possible Causes

RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2]
ELAC-1 [2CE1]
SEC-1 [1CE1]
Electronic Module 2
wiring of K3-1 signal from the ELAC 1 (2CE1) to the first terminal block
wiring of the DSI-49 signal from the ELAC 1 (2CE1) to the ELAC 1 (2CE1)
wiring of the K3-1B signal from the ELAC 1 (2CE1) to the first terminal block
wiring of the relay (36CE2) to the ELAC 1 (2CE1) and to the THS actuator (9CE)
wiring of the fault signal from the ELAC 1 (2CE1) to the first terminal block

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 31-32-00-810-932-A	Failure of the Discrete Links
TSM TASK 31-32-00-810-933-A	Failure of the Analog Links
AMM 24-41-00-861-002	Energize the Aircraft Electrical Circuits from the External Power
AMM 27-44-57-000-002	Removal of the Electronic Modules of the Pitch Trim Actuator
AMM 27-44-57-400-002	Installation of the Electronic Modules of the Pitch Trim Actuator
AIPC 27920803
ASM 279312
ASM 279313
AMM 27-93-34-000-001	Removal of the ELAC
AMM 27-93-34-400-001	Installation of the ELAC
ASM 279412
ASM 279413
AMM 27-94-34-000-001	Removal of the SEC
AMM 27-94-34-400-001	Installation of the SEC
AMM 27-96-00-740-001	BITE Test of the EFCS (Ground Scanning)
AMM 29-10-00-864-001	Depressurize the Green Hydraulic System
AMM 29-10-00-864-002	Depressurize the Yellow Hydraulic System
AMM 29-10-00-864-003	Depressurize the Blue Hydraulic System

3. Fault Confirmation
Subtask 27-93-00-700-102-A

A. Test
(1) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
(2) Make sure that the Green, Blue and Yellow hydraulic systems are not pressurized AMM 29-10-00-864-001, AMM 29-10-00-864-003 and AMM 29-10-00-864-002.
(3) On the panel 23VU:

release the FLT CTL/ELAC1 pushbutton switch.(On this pushbutton switch, the OFF legend comes on).

(4) Wait 30 seconds.
(5) On the panel 23VU:

push the FLT CTL/ELAC1 pushbutton switch.(On this pushbutton switch, the OFF legend goes off).

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

NOTE: Wait 60 seconds before you start the BITE test.

4. Fault Isolation
Subtask 27-93-00-810-094-A

A. If the BITE test gives the maintenance message:
THS ACTR SERVO MOT2 9CE OF ELAC1
(1) Remove the RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2] AIPC 27920803.
(2) Do a check of the resistance between pin X1 and X2 of the relay.
(a) if the resistance is less than 280 ohms:

replace the RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2] .
replace the ELAC-1 [2CE1] AMM 27-93-34-000-001 AMM 27-93-34-400-001.

(b) If the resistance is more than 400 ohms:

replace the RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2] .

install the RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2]
see Para (3).

(3) If the fault continues:

replace the ELAC-1 [2CE1] , AMM 27-93-34-000-001 and AMM 27-93-34-400-001.

(4) If the fault continues:

do the trouble shooting procedure (Ref. TSM TASK 31-32-00-810-932) related to the DSI 24 discret input signal of the ELAC 1 and SEC 1 ASM 279312 ASM 279313 ASM 279412 ASM 279413 and
do the trouble shooting procedure (Ref. TSM TASK 31-32-00-810-933) related to the ANI 2-3 analog input signal of the ELAC 1 and SEC 1 ASM 279312 and ASM 279412.

(5) If the fault continues:

replace the SEC-1 [1CE1] , AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

(6) If the fault continues:

replace the RELAY-PITCH TRIM ACTUATOR MOTOR 2 SPLY [36CE2] Ref. IPC 27920803.

(7) If the fault continues:

replace the Electronic Module 2 , AMM 27-44-57-000-002 and AMM 27-44-57-400-002.

(8) If the fault continues:

do a check of the wiring of K3-1 signal from the ELAC 1 (2CE1) to the first terminal block COM part and MON part ASM 279312.

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

do a check of the wiring of the DSI-49 signal from the ELAC 1 (2CE1) to the ELAC 1 (2CE1) COM part and MON part ASM 279312.

1 If there is no continuity, repair the wiring.
2 If there is continuity:

do a check of the wiring of the K3-1B signal from the ELAC 1 (2CE1) to the first terminal block, ASM 279312.

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

do a check and repair the wiring of the relay (36CE2) to the ELAC 1 (2CE1) and to the THS actuator (9CE), wiring of the fault signal from the ELAC 1 (2CE1) to the first terminal block, ASM 279312.

Subtask 27-93-00-700-103-A

B. Do the tests given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:27:58 UTC