P0743

DTC P0743 TORQUE CONVERTER CLUTCH CIRCUIT ELECTRICAL (SHIFT SOLENOID VALVE SL)

CIRCUIT DESCRIPTION

DTC Detecting Condition:

The shift solenoid valve SL is turned ON and OFF by signals from the ECM to control the hydraulic pressure acting on the lock-up relay valve, which then controls operation of the lock-up clutch.

Fail safe function:
If the ECM detects a malfunction, it turns the shift solenoid valve SL OFF.

MONITOR DESCRIPTION

Monitor Strategy:

Typical Enabling Conditions:

Typical Malfunction Thresholds:

Based on the signals from the Throttle Position Sensor, the Airflow Meter and the Crankshaft Position Sensor, the ECM sends a signal to the SL Solenoid Valve to regulate the hydraulic pressure and provide smoother gearshifts. The shift-solenoid valve SL responds to commands from the ECM. The valve controls the look-up relay valve to perform the torque-converter lock-up function. If the ECM detects an open or short circuit for shift-solenoid SL, it will illuminate the MIL and store the DTC.

Wiring Diagram:

Step 1:

Step 2 - 3:

INSPECTION PROCEDURE