P0740
DESCRIPTIONThe torque converter clutch solenoid valve is activated, with the gear in "D4", by the TCM in response to signals sent from the vehicle speed and throttle position sensors. Lock-up piston operation will then be controlled.
Lock-up operation, however, is prohibited when A/T 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.
CONSULT REFERENCE VALUE IN DATA MONITOR MODE
TCM TERMINALS AND REFERENCE VALUE
ON BOARD DIAGNOSIS LOGIC
DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE
CAUTION: If conducting this "DTC CONFIRMATION PROCEDURE" again, always turn ignition switch "OFF" and wait at least 5 seconds before continuing.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
With CONSULT-II
1) Turn ignition switch "ON".
2) Select "DATA MONITOR" mode for "ENGINE" with CONSULT-II and wait at least 1 second.
With GST
Follow the procedure "With CONSULT-II".
WIRING DIAGRAM - AT - TCV
DIAGNOSTIC PROCEDURE
COMPONENT INSPECTION
Torque converter clutch solenoid valve
Resistance check
- Check resistance between two terminals.
Operation check
- Check solenoid valve by listening for its operating sound while applying battery voltage to the terminal and ground.