Torque Converter Diagnosis

Torque Converter Diagnosis





Prior to torque converter installation, all diagnostic procedures must be followed. This is to prevent the unnecessary installation of new or remanufactured torque converters. Only after a complete diagnostic evaluation can the decision be made to install a new or remanufactured torque converter.

Begin with the normal diagnostic procedures as follows:

1. Preliminary Inspection

2. Know and Understand the Customer Concern

3. Verify the Concern - carry out the torque converter operation test

4. Carry out Diagnostic Procedures:
- Retrieve and record all DTCs. Refer to Diagnostics Diagnostics.
- Repair all non-transaxle related DTCs first.

- Repair all transaxle DTCs.

- Carry out Pressure Test. Refer to Special Testing Procedures Special Testing Procedures.

- Carry out Stall Speed Test. Refer to Special Testing Procedures Special Testing Procedures.

- Carry out diagnostic routines. Refer to Diagnosis By Symptom Diagnosis By Symptom.

- Use the index to locate the appropriate routine that best describes the symptom(s). The routine will list all possible components that may cause or contribute to the symptom. Check each component listed, diagnose and repair as required, before repairing the torque converter.


Torque Converter Operation Test

NOTE: The Torque Converter Clutch (TCC) will not engage if the Transmission Fluid Temperature (TFT) is below 0°C (32°F).

1. Using the scan tool, make sure that the TFT is within specification 43°C-47°C (109°F-117°F).

2. Accelerate the vehicle to 35-60 km/h (22-37 mph) and maintain a consistent speed.

3. Release the accelerator pedal to close the throttle and press the accelerator to partially open the throttle while monitoring the scan tool engine speed and TCCAMP_MES. The PID will read 0 when the TCC is released, and 1 when the TCC is applied. The engine speed will increase when the TCC is released and decrease when the TCC is applied.

4. If these actions do not occur, see Torque Converter Operations Concerns, refer to Diagnosis By Symptom Diagnosis By Symptom.