Lock-up Control

WARNING: This page is about a different car, the 2017 Chevrolet Spark. However, it is still accessible from the selected car via links, so may be relevant.

The torque converter clutch piston located in the converter is engaged to eliminate slip to increase power transmission efficiency. The control valve operation is performed by the torque converter clutch solenoid valve, which is controlled by a signal sent by the TCM. This control valve engages or releases the torque converter clutch piston directly using the pressure provided by the oil pump.

In lock-up released state, the torque converter clutch control valve is set into the unlocked state by the solenoid and the lock-up pressure apply is drained. In this way, the clutch piston is not coupled.

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the solenoid and lock-up apply pressure is generated. In this way, the clutch piston is pressed and coupled.