Loss of the Signal of the Right Yellow Elevator-Servocontrol Solenoid Valve by the SEC 1

TASK 27-30-00-810-844-A
Loss of the Signal of the Right Yellow Elevator-Servocontrol Solenoid Valve by the SEC 1

CAUTION: DO NOT SWAP FLIGHT CONTROL COMPUTERS. IF THERE IS A SHORT CIRCUIT, YOU WILL CAUSE DAMAGE TO A SERVICEABLE COMPUTER WHEN YOU SWAP THEM.

1. Possible Causes

solenoid valve of the servocontrol 34CE2
SERVO CTL-R ELEVATOR, INBD Y [34CE2]
SEC-1 [1CE1]
wiring of the SOL VLV2 signal from the servocontrol (34CE2) to the SEC1 (1CE1)
wiring from the SEC1 (1CE1) COM part to the SEC1 MON part
ELAC-2 [2CE2]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 27-34-51-000-001	Removal of the Elevator Servo Control
AMM 27-34-51-000-005	Removal of the Solenoid Valve of the Elevator Servo-Control Actuator
AMM 27-34-51-400-001	Installation of the Elevator Servo Control
AMM 27-34-51-400-004	Installation of the Solenoid Valve of the Elevator Servo-Control Actuator
AMM 27-93-34-000-001	Removal of the ELAC
AMM 27-93-34-400-001	Installation of the ELAC
ASM 279407
AMM 27-94-34-000-001	Removal of the SEC
AMM 27-94-34-400-001	Installation of the SEC
AMM 27-96-00-710-020	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 27-30-00-700-120-A

A. Test
(1) Do the operational test of the side stick assembly (Activation for the BITE test) AMM 27-96-00-710-020.

NOTE: Before you start the operational test procedure, release the FLT CTL/ELAC 1, FLT CTL/ELAC 2 and FLT CTL/SEC 2 pushbutton switches (on these pushbutton switches the OFF legends come on).

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

4. Fault Isolation
Subtask 27-30-00-810-085-A

A. If the test gives the maintenance message:
SEC1 MON OR WIRING TO R Y ELEV SOL VLV 34CE2
(1) Remove the SEC1 AMM 27-94-34-000-001.
(2) At the SEC1 receptacle, do a check of the resistance between the pin AB/15D and the pin AE/15G ASM 279407.

NOTE: The resistance must be between 40 and 100 Ohms.

(a) If the resistance is less than 40 Ohms:

at the inboard elevator servocontrol (34CE2), do a check of the resistance of the solenoid valve between the pin C/J and the pin C/U ASM 279407.

NOTE: The resistance must be between 40 and 100 Ohms.

1 If the resistance values are out of the specified limits:
a Replace the solenoid valve of the servocontrol 34CE2 AMM 27-34-51-000-005 and AMM 27-34-51-400-004.
b Do again a check of the resistance of the solenoid valve between the pin C/J and the pin C/U of the inboard elevator servocontrol (34CE2) (40 to 100 Ohms).

If the resistance values are out of the specified limits:
. Replace the SERVO CTL-R ELEVATOR, INBD Y [34CE2] AMM 27-34-51-000-001 and AMM 27-34-51-400-001.
. Replace the SEC-1 [1CE1] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.
If the resistance values are in the specified limits:
Replace the SEC-1 [1CE1] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

2 If the resistance values are in the specified limits:
a Repair the wiring of the SOL VLV2 signal from the servocontrol (34CE2) to the SEC1 (1CE1), from the pin C/J to the pin AB/15D and from the pin C/U to the pin AE/15G ASM 279407:
b Replace the SEC-1 [1CE1] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.
(b) If the resistance is more than 100 Ohms:

at the inboard elevator servocontrol (34CE2), do a check of the resistance of the solenoid valve between the pin C/J and the pin C/U ASM 279407.

NOTE: The resistance must be between 40 and 100 Ohms.

If the resistance values are out of the specified limits:
. Replace the SERVO CTL-R ELEVATOR, INBD Y [34CE2] AMM 27-34-51-000-001 and AMM 27-34-51-400-001.
. Install the SEC1 AMM 27-94-34-400-001.
If the resistance values are in the specified limits:
Install the SEC1 AMM 27-94-34-400-001.

2 If the resistance values are in the specified limits:
a Repair the wiring of the SOL VLV2 signal from the servocontrol (34CE2) to the SEC1 (1CE1), from the pin C/J to the pin AB/15D and from the pin C/U to the pin AE/15G ASM 279407:
b Install the SEC1 AMM 27-94-34-400-001.
(c) If the resistance values are in the specified limits:

See Para. (3).

(3) At the SEC1 receptacle, do a check of the insulation between pin AE/15G (pin AB/15D) and the ground.

NOTE: The resistance must be more than 100 Meghoms.

(a) If the resistance is more than 100 Megohms:

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

1 If the fault continues:

Replace the solenoid valve AMM 27-34-51-000-005 and AMM 27-34-51-400-004.

2 If the fault continues:

Replace the SERVO CTL-R ELEVATOR, INBD Y [34CE2] AMM 27-34-51-000-001 and AMM 27-34-51-400-001.

3 do a check of the wiring from the SEC1 (1CE1) COM part to the SEC1 MON part, from the pin AB/12F to the pin AE/15E ASM 279407:
a If the wiring is correct:

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

b If the wiring is not correct:

repair it
install the SEC1 AMM 27-94-34-400-001.

(b) If the resistance is less than 100 Meghoms:

At the SERVO CTL-R ELEVATOR, INBD Y [34CE2] , do a check of the insulation between pin C/U (pin C/J) and the ground.

1 If the resistance is less than 100 Megohms:

Replace the solenoid valve AMM 27-34-51-000-005 and AMM 27-34-51-400-004.

a Do again a check of the insulation of the solenoid valve between pin C/U (pin C/J) and the ground.

If the resistance is less than 100 Megohms:
.Replace the SERVO CTL-R ELEVATOR, INBD Y [34CE2] AMM 27-34-51-000-001 and AMM 27-34-51-400-001.
.Replace the SEC-1 [1CE1] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.

2 If the resistance is more than 100 Meghoms:
a Repair the wiring of the solenoid valve signal from the SERVO CTL-R ELEVATOR, INBD Y [34CE2] to the SEC-1 [1CE1] .
b Replace the SEC-1 [1CE1] AMM 27-94-34-000-001 and AMM 27-94-34-400-001.
(4) If the fault continues:

replace the ELAC-2 [2CE2] , (MON part relay K2), AMM 27-93-34-000-001 and AMM 27-93-34-400-001.

Subtask 27-30-00-700-121-A

B. Do the tests given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:27:34 UTC