Output Shaft Speed (OSS) Sensor

2009 Mercury Milan Premier, 3.0 1, AWDSECTION Output Shaft Speed (OSS) Sensor
WARNING: This page is about a different car, the 2008 Mercury Milan and 2008 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The OSS sensor is located in the transaxle housing above the rotor in the differential.

The OSS sensor is an inductive sensor which detects the vehicle speed by means of a rotor on the differential.

The signal is used for the following functions among other things:

  • to determine the shift timing,
  • to supply the vehicle speed input signal for the TCM.

If the OSS sensor fails, the signal of the TSS sensor is used as a substitute signal.

Fig 1: Transmission Range (TR) Sensor
GF0029693Courtesy of FORD MOTOR CO.

The Transmission Range (TR) sensor is located on the manual control lever shaft on the transaxle housing.

When the manual control lever shaft is moved by means of the selector lever cable, an engagement pin in the inner ring of the TR sensor moves through the different positions. The signals are transmitted to the TCM, the reversing lamps and the starter inhibitor relay.

NOTE: Correct operation of the TR sensor is only guaranteed when the manual selector lever cable is adjusted correctly.

The signals of the TR sensor are used for the following functions:

  • to recognize the selector lever position.
  • to actuate the starter inhibitor relay.
  • to actuate the reversing lamps.

No substitute signal is available for the TR sensor.

If the connection is cut, the vehicle cannot be started.

RENDER: 1.0x

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