Drive and Low Range - Torque Converter Clutch Applied (Hydraulic Circuits): Notes

WARNING: This page is about a different variant/trim than selected.

When the transmission control module (TCM) determines that the engine and transmission are operating properly to engage the torque converter clutch (TCC), the TCM energizes the VFS TCC control solenoid E valve and regulates the current command to the VFS TCC control solenoid E valve.

The Following events occur in order to apply the torque converter clutch:

Stage 1

The TCM increases the current command to output 200kPa from the TCC Solenoid. The TCC Fault Valve will shift over first around 70kPa of solenoid pressure then the TCC Control Valve around 150kPa of solenoid pressure. With the two valves pushed over this allows the output of the TCC Regulator Valve to feed into the TCC Control Valve into the Apply side of the Torque Converter. The Release side of the Torque converter is free to flow through the TCC Control Valve into the TCC Fault valve to exhaust. It also allows Converter Feed to bypass the Torque Converter and flow directly into the Oil Cooler.

Stage 2

Once Stage 1 is complete the TCM will then command a increasing ramp in current which increases the pressure at the Torque Converter Clutch. As the pressure increases the Torque Converter Clutch will apply in a controlled manner based on a Clutch Apply Profile. At this point the Torque Converter Clutch locks the engine to the transmission turbine.