Transmission Control Systems

To diagnose the computer controlled portion of the transmission refer to Computers and Control Systems / System Diagnosis / Diagnostic System Check. Testing and Inspection

The diagnosis of the Torque Converter Clutch (TCC) system is covered in Chart C-8A. If the Powertrain Control Module (PCM) detects a problem with the Vehicle speed Sensor (VSS) signal, diagnostic trouble code (DTC) 24 or 72 should set. In this case, refer to the appropriate chart.

If any of the following diagnostic trouble codes are set, TCC may not be allowed to engage and transaxle shifting may be incorrect. Repair any existing diagnostic trouble codes and then recheck TCC or shift control.


DTC 16 - System low voltage.

DTC 21 - Throttle Position (TP) Sensor Circuit High.

DTC 22 - Throttle Position (TP) Sensor Circuit Low.

DTC 24 - Vehicle Speed Sensor (VSS) Circuit No Signal Voltage.

DTC 34 - Manifold Absolute Pressure (MAP) Sensor Circuit (Signal Voltage Low).

DTC 35 - Idle Speed Error.

DTC 58 - TFT Sensor Circuit (High Temp).

DTC 59 - TFT Sensor Circuit (LOW TEMP).

DTC 72 - VSS Circuit Error.

DTC 79 - Transmission Fluid Overtemp.

DTC 80 - Transmission Component.

DTC 96 - Trans System Voltage Low.