Procedure

PROCEDURE
In order to properly diagnose the Torque Converter Clutch (TCC) system, perform all of the electrical testing first. Then do the hydraulic testing.
The TCC is applied by fluid pressure, which is controlled by a solenoid inside of the automatic transmission assembly. The solenoid is energized by completing an electrical circuit through a combination of switches and sensors.

Functional Check Procedure
1. Install a tachometer or a scan tool.
2. Operate the vehicle until you reach proper operating temperature.
3. Drive the vehicle at 80-88 km/ (50-55 mph) with a light throttle (road load).
4. Maintaining the throttle, lightly touch the brake pedal. Check for the release of the TCC and a slight increase in engine speed (RPM).
5. Release the brake. Slowly accelerate and check for a re-apply of the converter clutch and a slight decrease in engine speed (RPM).