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TCC Controls

Most Hydra-matic 4T60-E transaxle models also use two solenoid valves to control TCC apply and release. The first solenoid valve in this system is the pressure controlling solenoid. It is a Pulse Width Modulation (PWM) solenoid valve that acts as a direct bias on the converter clutch regulator valve. This solenoid valve is normally open.

The other solenoid valve is an ON/OFF solenoid valve with a 2-port design that is identical to the two shift solenoid valves. This type of system provides for accurate control of regulated apply pressure that feeds the apply side of the torque converter clutch plate.