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P0744


P0744 TORQUE CONVERTER





Description
- This is detected when torque converter clutch is not engaged under an electrically normal condition of torque converter clutch solenoid valve.
- This DTC is not caused by an electrical malfunction (circuit open or short) but is caused by a mechanical malfunction (control valve clogging, solenoid valve sticking, and others).




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE

CAUTION:
Always drive vehicle at a safe speed.
1.PRECONDITIONING
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.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT-III
1. Start the engine.
2. Select "Data Monitor" in "TRANSMISSION".
3. Select "RANGE", "ATF TEMP SEN", "ACC PEDAL OPEN" and "VEHICLE SPEED".
4. Drive the vehicle.
5. Maintain the following conditions for 10 seconds or more.





6. Stop the vehicle.
7. Select "Self Diagnostic Results" in "TRANSMISSION".
With GST
Follow the procedure "With CONSULT-III".
Is "P0744" detected?
YES - Go to P0744.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK LINE PRESSURE
Perform line pressure test. Initial Inspection and Diagnostic Overview.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace damaged parts. Initial Inspection and Diagnostic Overview.
2.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
1. Turn ignition switch OFF.
2. Disconnect CVT unit connector.
3. Check torque converter clutch solenoid valve. P0744.
Is the inspection result normal?
YES - GO TO 3.
NO - Torque converter clutch solenoid valve is malfunctioning. Replace transaxle assembly. Exploded View.
3.CHECK LOCK-UP SELECT SOLENOID VALVE
Check lock-up select solenoid valve. P0744.
Is the inspection result normal?
YES - GO TO 4.
NO - Lock-up select solenoid valve is malfunctioning. Replace transaxle assembly. Exploded View.
4.CHECK PRIMARY SPEED SENSOR SYSTEM
Check primary speed sensor system. P0715.
Is the inspection result normal?
YES - GO TO 5.
NO - Repair or replace damaged parts.
5.CHECK SECONDARY SPEED SENSOR SYSTEM
Check secondary speed sensor system. P0720.
Is the inspection result normal?
YES - GO TO 6.
NO - Repair or replace damaged parts.
6.CHECK INTERMITTENT INCIDENT
Intermittent Incident.
Is the inspection result normal?
YES - Replace transaxle assembly. Exploded View.
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. Exploded View.




Component Inspection (Lock-up Select Solenoid Valve)
1.CHECK LOCK-UP SELECT SOLENOID VALVE
Check resistance between CVT unit harness connector terminal and ground.





Is the inspection result normal?
YES - INSPECTION END
NO - Lock-up select solenoid valve is malfunctioning. Replace transaxle assembly. Exploded View.