Nissan Versa Sedan Service ManualTransmission & driveline » Transaxle & transmission (TM)
P0744 Torque converter
P0744 Torque converter
Description
This DTC is detected when the torque converter clutch solenoid valve is electrically normal but the torque converter clutch does not engage. This is not due to an electrical malfunction (circuit open or shorted), but is instead due to a mechanical malfunction (sticking of the control valve, malfunction of the solenoid, etc.).
DTC Logic
DTC DETECTION LOGIC
| DTC | Trouble diagnosis name | DTC detection condition | Possible causes |
| P0744 | Torque Converter Clutch Circuit Intermittent | The following diagnosis conditions
are met, and the torque
converter slip speed is at or
above a set value (40 rpm + Vehicle
speed / 2) continuously for
30 seconds or more. - Diagnosis condition - Lock-up pressure difference: More than Max. lock-up pressure difference × 0.95 |
- Torque converter clutch solenoid
valve - Control valve assembly - Torque converter |
DTC REPRODUCTION PROCEDURE
CAUTION: Be careful of the driving 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
- Drive the vehicle.
- Maintain the following conditions for 35 seconds or more.
Selector lever : D position
Vehicle speed : 45 km/h (28 MPH) or more
3. Stop the vehicle.
4. Check the first trip DTC.
Is "P0744" detected?
YES >> Go to TM, "Diagnosis Procedure".
NO >> Check intermittent incident. Refer to GI, "Intermittent Incident".
Diagnosis Procedure
1.CHECK LINE PRESSURE
Perform line pressure test. Refer to TM, "Work Procedure".
Is the check result normal?
YES >> GO TO 2.
NO >> Repair or replace the malfunction items.
2.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
- Turn ignition switch OFF.
- Disconnect the A/T unit connector.
- Check the torque converter clutch solenoid valve. Refer to TM, "Component Inspection (Torque Converter Clutch Solenoid Valve)".
Is the check result normal?
YES >> Check intermittent incident. Refer to GI, "Intermittent Incident".
NO >> Repair or replace the malfunction items.
Component Inspection (Torque Converter Clutch Solenoid Valve)
1.CHECK TORQUE CONVERTER CLUTCH SOLENOID VALVE
Check the resistance between the A/T unit connector terminal and ground.
Is the check result normal?
YES >> INSPECTION END
NO >> There is a malfunction of the torque converter clutch solenoid valve. Replace the transaxle assembly. Refer to TM, "Removal and Installation".