Circuit Description
The automatic transmission input shaft speed (AT ISS) sensor provides transmission input speed to the transmission control module (TCM). The AT ISS sensor is a permanent magnet (PM) generator. The sensor mounts into the transmission case and maintains a slight air gap between the sensor and the forward clutch housing. The PM generator produces an AC voltage as the forward clutch housing rotor teeth pass through the magnetic field of the sensor. The AC voltage level increases as the turbine shaft speed increases. The TCM converts the AC voltage into a digital signal. The TCM determines actual turbine speed using the digital signal. The TCM uses the input speed to calculate torque converter slip speed, and gear ratios.
When the TCM detects an unreasonably large change in the input speed, in a very short period of time, then DTC P0716 sets. DTC P0716 is a type B DTC.