Torque Converter Clutch Pulse Width Modulation Solenoid Valve

The PCM controls the Torque Converter Clutch Pulse Width Modulation Solenoid valve (TCC PWM Sol valve) by varying its operating duty cycle (ON/OFF time) from 0% to 100%. Until the transmission is operating in 3rd gear, the TCC PWM Sol valve is OFF. In this state, filtered PWM feed pressure flows at maximum pressure through the solenoid and into the PWM circuit.

When the TCC PWM Sol valve is energized, the valve operates at 32 Hz (cycles per second) and from 0% to 100% duty cycle depending on vehicle operation. The TCC PWM Sol valve is enabled to modulate the amount of PWM feed pressure passing through the solenoid, sending it to the converter clutch regulator valve. At 0% duty cycle, the torque converter clutch applies at maximum capacity. At 100% duty cycle the clutch applies at minimum capacity.