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
1.Turn ignition switch ON.
2.Select "Data Monitor" in "TRANSMISSION".
3.Start engine and maintain the following condition for at least 30 seconds.

ACC PEDAL OPEN : More than 1.0/8
RANGE : "D" position
VEHICLE SPEED : Constant speed of more than 40 km/h (25 MPH)

With GST
Follow the procedure "With CONSULT".
Is "P0744" detected?
YES- Go to Diagnosis Procedure (see below).
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. P0740.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace damaged parts.

3. CHECK LOCK-UP SELECT SOLENOID VALVE

Check lock-up select solenoid valve. P1740.
Is the inspection result normal?
YES- GO TO 4.
NO- Repair or replace damaged parts.

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. CHECK DTC (TCM)

With CONSULT
1.Perform "DTC CONFIRMATION PROCEDURE". .
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. Transmission Assembly (2WD) or Transmission Assembly (AWD).
NO- Check intermittent incident. Intermittent Incident.