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 malfunctions (circuits open or shorted), but also by mechanical malfunctions 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.

NOTE:
Immediately after performing any "DTC CONFIRMATION PROCEDURE", always turn ignition switch OFF.
Then wait at least 10 seconds before performing the next test.
1.CHECK DTC DETECTION
With CONSULT-III
1. Turn ignition switch ON.
2. Select "Data Monitor" in "TRANSMISSION".
3. Start engine and maintain the following condition for at least 30 seconds.





With GST
Follow the procedure "With CONSULT-III".
Is "P0744" detected?
YES - Go to P0744.
NO - Check intermittent incident. Intermittent Incident.




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 - 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 - Replace transaxle assembly. Exploded View.
4.CHECK SECONDARY SPEED SENSOR SYSTEM
Check secondary speed sensor system. P0720.
Is the inspection result normal?
YES - GO TO 5.
NO - Repair or replace damaged parts.
5.CHECK PRIMARY SPEED SENSOR SYSTEM
Check primary speed sensor system. P0715.
Is the inspection result normal?
YES - GO TO 6.
NO - Repair or replace damaged parts.
6.DETECT MALFUNCTIONING ITEMS
Check TCM connector pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?
YES - Replace TCM. 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 connector terminal and ground.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace transaxle assembly. Exploded View.




Component Inspection (Lock-up Select Solenoid Valve)
1.CHECK LOCK-UP SELECT SOLENOID VALVE





Check resistance between CVT unit connector terminal and ground.





Is the inspection result normal?
YES - INSPECTION END
NO - Replace transaxle assembly. Exploded View.