A vehicle’s speed sensor is a monitoring device that measures the output of a transmission or transaxle in terms of wheel speed.
This information is used by the engine control module to adjust the automobile’s performance automatically in order to achieve optimum levels.
Speed sensors are located in the transmission or transaxle of a vehicle, Over time, this location exposes them to potential metal contamination and even water damage.
A malfunctioning speed sensor can cause inaccurate speed readings to be displayed on the speedometer and lead to erroneous data being relayed to the engine control module, causing potential stalls, gear shifting issues and multiple performance problems.
They can work by measuring position from GPS and divide by time to give average speed. Or they can work by measuring relative to the water or air. Or for cars, they can simply count number of turns per unit of time (angular speed) and multiply by the radius of the wheel.