P0740

P0740 TORQUE CONVERTER

Description

- Torque converter clutch solenoid valve is installed to control valve.
- Torque converter clutch solenoid valve adjusts oil pump discharge pressure to an optimum level according to the driving conditions.
- The adoption of an N/L type (normal low) torque converter clutch solenoid valve enables generation of a control oil pressure when a voltage is not applied to the coil.
- Torque converter clutch solenoid valve is controlled by TCM according to signals transmitted from vehicle speed sensor and accelerator pedal position sensor.
- Lock-up is prohibited when CVT fluid temperature is low.
- When accelerator pedal is depressed (throttle opening angle is less than 2.0/8) in the lock-up state, engine speed does not suddenly change. If engine speed changes suddenly, lock-up is not applied.


DTC Logic


DTC DETECTION LOGIC







DTC CONFIRMATION PROCEDURE


CAUTION:
Always drive vehicle at a safe speed.

1. PRECONDITIONING (PART 1)

Immediately after performing any "DTC CONFIRMATION PROCEDURE", always turn ignition switch OFF.
Then wait at least 10 seconds before performing the next test.
- GO TO 2.

2. PRECONDITIONING (PART 2)

With CONSULT
1.Start the engine.
2.Select "Data Monitor" in "TRANSMISSION".
3.Select "ATF TEMP SEN".
Is "ATF TEMP SEN" value 2.17 V or less?
YES- GO TO 3.
NO- 1.Warm up transaxle.
2.GO TO 3.

3. PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT
1.Start the engine.
2.Select "Data Monitor" in "TRANSMISSION".
3.Select "VEHICLE SPEED".
4.Drive the vehicle.
5.Maintain the following conditions for 5 seconds or more.

VEHICLE SPEED : More than 40 km/h (25 MPH)

6.Stop the vehicle.
7.Select "Self Diagnostic Results" in "TRANSMISSION".
With GST
Follow the procedure "With CONSULT".
Is "P0740" detected?
YES- Go to .
NO- INSPECTION END


Diagnosis Procedure


1. CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE CIRCUIT

1.Turn ignition switch OFF.
2.Check resistance between TCM connector terminal and ground.





Is the inspection result normal?
YES- Check intermittent incident. Intermittent Incident.
NO- GO TO 2.

2. CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE

1.Disconnect CVT unit connector.
2.Check torque converter clutch solenoid valve. .
Is the inspection result normal?
YES- GO TO 3.
NO- Torque converter clutch solenoid valve is malfunctioning. Replace transaxle assembly. Refer to
Exploded View.

3. CHECK HARNESS BETWEEN TCM AND CVT UNIT (TORQUE CONVERTER CLUTCH SOLENOID

VALVE) (PART 1)
1.Disconnect TCM connector.
2.Check continuity between TCM vehicle side harness connector terminal and CVT unit vehicle side harness connector terminal.





Is the inspection result normal?
YES- GO TO 4.
NO- Repair or replace damaged parts.

4. CHECK HARNESS BETWEEN TCM AND CVT UNIT (TORQUE CONVERTER CLUTCH SOLENOID

VALVE) (PART 2)
Check continuity between TCM vehicle side harness connector terminal and ground.





Is the inspection result normal?
YES- Check intermittent incident. Intermittent Incident.
NO- Repair or replace damaged parts.


Component Inspection (Torque Converter Clutch Solenoid Valve)


1. CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE

Check resistance between CVT unit harness connector terminal and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- Torque converter clutch solenoid valve is malfunctioning. Replace transaxle assembly. Refer to
Exploded View.