Torque Converter Clutch (TCC)

The ECM controls a solenoid (mounted on automatic transmission) to allow torque converter to directly connect engine to transmission, providing direct drive. When vehicle speed is high enough, ECM energizes TCC solenoid and engine is mechanically coupled to transmission. When operating conditions indicate that transmission should operate as normal (during rapid acceleration or deceleration), solenoid is de-energized. The transmission also returns to normal automatic operation when brake pedal is depressed.