Torque Converter Hydraulic Circuits

WARNING: This page is about a different car, the 2008 Mercury Sable, 2008 Ford Taurus X, and 2008 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.

The PCM controls the TCC solenoid. The TCC solenoid applies hydraulic pressure to the TCC control and regulator apply valves through the TCC SOL SIG circuit. Regulated DRIVE 2 pressure from the multiplex shift valve is directed to the TCC control valve by the TCC regulator apply valve through the REG APPLY circuit. The TCC control valve directs pressure from the REG APPLY circuit to the TCC APPLY circuit to apply the clutch.

The transmission fluid returns to the TCC control valve through the TCC RELEASE hydraulic circuit. The TCC control valve opens the TCC RELEASE circuit to exhaust, so the TCC RELEASE circuit is not pressurized when the TCC is applied.

Fig 1: Identifying Torque Converter Hydraulic Circuits (TCC Applied)

Courtesy of FORD MOTOR CO.

When the TCC is released, The TCC solenoid does not apply hydraulic pressure to the TCC control or regulator apply valves. The TCC control valve, in this position, directs hydraulic pressure from the CONV FD circuit to the torque converter through the TCC RELEASE hydraulic circuit and it returns to the TCC control valve through the TCC APPLY circuit.

For torque converter description and function, refer to Torque Converter .

Fig 2: Identifying Torque Converter Hydraulic Circuits

Courtesy of FORD MOTOR CO.