P0740

P0740 TORQUE CONVERTER





Description
- The torque converter clutch solenoid valve is activated by the TCM in response to signals sent from the vehicle speed and accelerator pedal position sensors. Lock-up piston operation will then be controlled.
- Lock-up operation, however, is prohibited when CVT fluid temperature is too low.
- When the accelerator pedal is depressed (less than 2.0/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.




DTC Logic

DTC DETECTION LOGIC






DTC CONFIRMATION PROCEDURE

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. Wait at least 10 consecutive seconds.
3. Perform "Self Diagnostic Results" in "TRANSMISSION".
With GST
Follow the procedure "With CONSULT-III".
Is "P0740" detected?
YES - Go to P0740.
NO - Check intermittent incident. Intermittent Incident.




Diagnosis Procedure
Regarding Wiring Diagram information, [1][2]Electrical Diagrams.
1.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE CIRCUIT





1. Turn ignition switch OFF.
2. Disconnect TCM connector.
3. Check resistance between TCM vehicle side harness connector terminal and ground.





Is the inspection result normal?
YES - GO TO 5.
NO - GO TO 2.
2.CHECK HARNESS BETWEEN TCM AND CVT UNIT (TORQUE CONVERTER CLUTCH SOLENOID VALVE) (PART 1)

1. Disconnect CVT unit 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 3.
NO - Repair or replace damaged parts.
3.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 - GO TO 4.
NO - Repair or replace damaged parts.
4.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
Check torque converter clutch solenoid valve. P0740.
Is the inspection result normal?
YES - GO TO 5.
NO - Replace transaxle assembly. Exploded View.
5.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.