P0744

P0744 TORQUE CONVERTER





Description
This malfunction is detected when the torque converter clutch does not lock-up as instructed by the TCM. This is not only caused by electrical malfunction (circuits open or shorted), but also by mechanical malfunction such as control valve sticking, improper solenoid valve operation, etc.




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE

CAUTION:
Always drive vehicle at a safe speed.
1.PREPARATION BEFORE WORK
If another "DTC CONFIRMATION PROCEDURE" occurs just before, turn ignition switch OFF and wait for at least 10 seconds, then perform the next test.
- GO TO 2.
2.CHECK DTC DETECTION
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 condition for 30 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 SEE Diagnosis Procedure.
NO - INSPECTION END




Diagnosis Procedure
1.CHECK LINE PRESSURE
Perform line pressure test. Line Pressure Test.
Is the inspection result normal?
YES - GO TO 2.
NO - Repair or replace damaged parts. Line Pressure Test.
2.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
1. Disconnect CVT unit connector.
2. Check continuity between CVT unit connector terminal and ground.





Is the inspection result normal?
YES - GO TO 3.
NO - GO TO 6.
3.CHECK LOCK-UP SELECT SOLENOID VALVE
Check lock-up select solenoid valve. SEE Component Inspection (Lock-up Select Solenoid Valve), "Component Inspection (Lock-up Select Solenoid
Valve)".
Is the inspection result normal?
YES - GO TO 4.
NO - Repair or replace damaged parts.
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 DTC (TCM)
With CONSULT-III
1. Perform "DTC CONFIRMATION PROCEDURE". SEE DTC Logic.
2. Select "Self Diagnostic Results" in "TRANSMISSION".
Is "P0744" detected?
YES-1 (Only "P0744" is detected)-There is a malfunction of the torque converter clutch solenoid valve.
Replace the control valve. Removal And Installation.
YES-2 ("P0744" and other than "P0744" are detected)-Replace the transaxle assembly. Exploded View Removal And Installation, Removal And Installation (AWD).
NO - Check intermittent incident. Intermittent Incident.




Component Inspection (Lock-up Select Solenoid Valve)

LOCK-UP SELECT SOLENOID VALVE
1.LOCK-UP SELECT SOLENOID VALVE
Check resistance between CVT unit connector terminal and ground.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace the transaxle assembly. Removal And Installation (2WD) or Removal And Installation (AWD).