Cutlass V6-191 3.1L VIN M SFI (1998)
Torque Converter Clutch Solenoid: Description and Operation
TORQUE CONVERTER CLUTCH SOLENOID VALVE
The Torque Converter Clutch Solenoid Valve (TCC Solenoid Valve) is a normally closed, Pulse Width Modulated (PWM) solenoid used to control
the apply and release of the converter clutch. The PCM operates the solenoid with a negative duty cycle at a fixed frequency of 42 Hz to control the
rate of TCC apply/release. The solenoid's ability to ramp the TCC apply and release pressures results in a smoother TCC operation.
When vehicle operating conditions are appropriate to apply the TCC, the PCM immediately increases the duty cycle to approximately 68%. The PCM
then ramps the duty cycle up to approximately 93% to achieve full TCC apply pressure. The rate at which the PCM increases the duty cycle controls
the TCC apply. Similarly, the PCM also ramps down the TCC solenoid duty cycle to control the TCC release.
Some operating conditions prevent or enable the TCC apply under various conditions. Also if the PCM receives a high voltage signal from the brake
switch, indicating that the brake pedal is depressed, the PCM immediately releases the TCC.
Note that the duty cycles in the graph are for example only. Actual duty cycles vary depending on the vehicle application and the vehicle operating
conditions.
The TCC Solenoid valve resistance should measure between 10.4-10.8 ohms when measured at 20°C (68°F). The resistance would measure
approximately 16 ohms at 150°C (300°F).
