Overdrive Range, Fourth Gear - Torque Converter Clutch Applied (Without Touch Activated Power): Notes
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
The torque converter clutch applies during third or fourth gear operation after the powertrain control module (PCM) receives the appropriate input signals to energize the TCC control (PWM) solenoid. To apply the torque converter clutch, the following changes take place in the electrical and hydraulic systems: