Pacifica, 2003-2005

Output Speed Sensor


Description & Operation

The Output Speed Sensor is a two-wire magnetic pickup device that generates an AC signal as rotation occurs. It is threaded into the transaxle case. The Output Speed Sensor is sealed with an O-ring, and is considered a primary input to the Powertrain/Transmission Control.

The Output Speed Sensor provides information on how fast the output shaft is rotating. As the rear planetary carrier park pawl lugs pass by the sensor coil, an AC voltage is generated and sent to the PCM/TCM. The PCM/TCM interprets this information as output shaft rpm.

The PCM/TCM compares the input and output speed signals to determine the following:

Transmission gear ratio
Speed ratio error detection
CVI calculation

Vehicle Speed Signal

The vehicle speed signal is taken from the Output Speed Sensor. The PCM converts this signal into a pulse per mile signal and sends the vehicle speed message across the communication bus to the BCM. The BCM sends this signal to the Instrument Cluster to display vehicle speed to the driver. The vehicle speed signal pulse is roughly 8000 pulses per mile.

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Removal & Installation

  1. Disconnect battery negative cable.
  3. Raise vehicle on hoist.
  5. Disconnect output speed sensor connector.
  7. Unscrew and remove output speed sensor.
  9. Inspect speed sensor O-ring and replace if necessary.

To Install:

  1. Verify O-ring is installed into position.
  3. Install and tighten output speed sensor to 27 Nm (20 ft. lbs.).
  5. Connect speed sensor connector.
  7. Connect battery negative cable.