F 550 4WD Super Duty V8-6.0L DSL Turbo VIN P (2003)
Transmission Speed Sensor: Description and Operation
Output Shaft Speed Sensor
Output Shaft Speed (OSS) Sensor
The Output Shaft Speed (OSS) sensor detects the speed of the transmission output shaft. The sensor uses variations in a magnetic field caused by a
tone wheel to generate a pulse train output corresponding to shaft speed. The OSS tone wheel uses a repetitive pattern of three different angler
displacements between teeth. The pulse width order can be used to determine shaft rotation direction. The magnetic sensor element may be a Hall
sensor or a magneto-resistive pick-up. Due to the open collector design and the RC timing involved in the pull-up, the rising edge of the pulse train is
not a reliable edge for critical timing, only the falling edge. The pull-up is located in the PCM to provide a wetting current for the sensor connectors.
This applies specifically to the TorqShift.
