Circuit/System Description

WARNING: This page is about a different car, the 2011 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

Torque Converter Clutch (TCC) Solenoid

The torque converter clutch pulse width modulated (TCC PWM) solenoid is a normally closed solenoid used to control the apply and release of the converter clutch. When the vehicle operating conditions are appropriate to apply the TCC, the transmission control module (TCM) immediately increases the duty cycle to approximately 42 percent. The TCM then ramps the duty cycle to approximately 90 percent to achieve full TCC apply pressure. When the TCC is fully applied, the engine is coupled directly to the transmission through the TCC. The TCM normally allows a small amount of slip to occur. When the TCC is engaged, TCC slip speed is maintained at approximately 20-50 RPM.

The 1-2 Shift and 2-3 Shift Solenoids

The 1-2 shift solenoid (SS) valve and the 2-3 SS valves control transmission fluid pressure acting on the shift valves to position the valves for the appropriate gear. The 1-2 SS and the 2-3 SS valves are normally-open exhaust valves located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 SS valve and the 2-3 SS valve. The TCM commands the solenoid ON or OFF by switching the ground path. The TCM identifies a 1-2 SS valve or a 2-3 SS valve condition by monitoring the commanded gear versus gear ratio.