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Transmission Speed Sensor: Description and Operation

OUTPUT SHAFT SPEED SENSOR
The Output Shaft Speed Sensor (OSS), provides the Powertrain Control Module (PCM) with information about the rotational speed of an output shaft. The PCM uses the information to control and diagnose powertrain behavior. In some applications, the sensor is also used as the source of vehicle speed. The sensor may be physically located in different places on the vehicle, depending upon the specific application. The design of each speed sensor is unique and depends on which powertrain control feature uses the information generated.