Torque Converter Clutch Diagnosis

In order to properly diagnose the Torque Converter Clutch (TCC) system, perform all electrical testing first. Then perform the hydraulic testing.

The Torque Converter Clutch (TCC) is applied by fluid pressure, which is controlled by a solenoid valve. This solenoid valve is located inside of the automatic transmission assembly.

The vehicle PCM energizes the solenoid valve.

Functional Check Procedure

1. Set up the TECH 1 or other scan tool in order to read the engine.

2. Operate the vehicle until you have reached the proper operating temperature.

3. Drive the vehicle at 80-88 km/h (50-55 mph) with a light throttle (road load).

4. Maintaining throttle speed, lightly touch the brake pedal. Check for the release of the TCC and a slight increase in engine speed.

5. Release the brake and slowly accelerate. Check for a reapply of the converter clutch and a slight decrease in engine speed.

6. To properly diagnose the Torque Converter Clutch (TCC) system, first perform all electrical testing and then test the hydraulic system.

^ For diagnosis of the TCC hydraulic controls, refer to the Fluid Flow and Circuit Descriptions, and the Wiring Diagrams.

^ Refer to the DTC tables. Testing and Inspection