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Speed Sensor

  1. Raise and support front of vehicle. Set parking brake and block rear wheels. Back probe voltmeter or test light positive probe into Yellow/Black wire terminal at 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. Battery voltage should be as shown in SPEED SENSOR VOLTAGE CHECK table.
    SPEED SENSOR VOLTAGE CHECK

    Speed Voltage
    Below 11 MPH Yes
    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.
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