Turbine Shaft Speed (TSS) Sensor
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The turbine shaft speed (TSS) sensor is a magnetic pickup, that sends a signal to the PCM to indicate transmission turbine shaft speed. The TSS is mounted externally on the case. The PCM uses the TSS signal to help determine appropriate operating pressure and torque converter clutch (TCC) operation.