Torque Converter Clutch Solenoid: Description and Operation

TORQUE CONVERTER CLUTCH SOLENOID VALVE (DTC: P1550)
The Engine Control Module (ECM) controls torque converter clutch solenoid valve to cancel the lock-up condition of A/T When the solenoid valve is turned on lock-up is cancelled. When the solenoid valve is turned off, Apr lock-up is operational.
Conditions for lock-up cancel:
^ Throttle valve is fully closed (idling or deceleration)
^ Engine coolant temperature is below 60°C (140°F)
^ Vehicle speed is less than 64 km/h (40 MPH)
^ During high-load operation