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Auto. Trans.

  1. Raise and support front of vehicle. Connect voltmeter or test light positive probe into Yellow/Black wire terminal at the control unit connector.
  2. Connect 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.
  3. If no voltage was present during test, check for bad electrical connection, fuse or faulty speed sensor. Replace or repair as necessary and retest.
SPEED SENSOR VOLTAGE CHECK

Speed Voltage
Below 11 MPH Yes
Above 16 MPH No