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Speed Sensor

  1. Jack up and support the front of vehicle. Push the voltmeter or test light positive probe into the Yellow/Black wire terminal at the control unit connector.
  2. Connect the negative probe to ground. Start engine. Place vehicle in second position (gear selector in 2 position) and accelerate slowly. Voltage should be as shown in table.
    SPEED SENSOR VOLTAGE CHECK

    Application Speed Voltage
    Man. Trans. Below 6 MPH Yes
    Man. Trans. Above 12 MPH No
    Auto. Trans. Below 11 MPH Yes
    Auto. Trans. Above 16 MPH No
  3. If voltmeter readings do not correspond to above MPH ranges, install a new speed sensor and retest. If there was no voltage during step 2), check for bad electrical connection, fuse or faulty speed sensor. Replace or repair as necessary and retest.