Torque Converter Diagnosis

Torque Converter Diagnosis





NOTE: If the torque converter is replaced, use the scan tool and follow the on-screen instructions and perform the Misfire Monitor Neutral Profile Correction procedure.

Perform all diagnostic procedures prior to torque converter installation. This prevents the unnecessary installation of new or remanufactured torque converters. Only after a complete diagnostic evaluation can the decision be made to install a new torque converter.

Torque Converter Operation Test

NOTE: Always drive the vehicle in a safe manner according to driving conditions and obey all traffic laws.

The Torque Converter Operation Test verifies the Torque Converter Clutch (TCC) control system and the torque converter are operating correctly.

1. Connect a scan tool to the vehicle.

2. Perform a self-test and check for DTCs.

3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds in the D position.

4. After normal operating temperature is reached, maintain a constant speed of about 56 km/h (35 mph) in 5th gear for 10 seconds.

5. Release the accelerator pedal and monitor the scan tool TP1 PID voltage to approximately 1.25 volts or 25% throttle.

6. Monitor the TCC_OSC# and RPM# PID. The torque converter should release and engine rpm should increase before the 5-4 shift occurs.