Torque Converter Clutch Solenoid: Description and Operation

The ECM controls torque converter lock-up through a solenoid mounted in the automatic transmission.
- When the vehicle reaches a specified speed, the ECM energizes the solenoid mechanically coupling the torque converter and the engine to the transmission.
- When the brake is applied--or other conditions indicate that the transmission should operate as a normal, fluid coupled transmission--the solenoid is de-energized.