Vehicle Speed Sensor: Testing and Inspection

1. Raise and support front of vehicle, block rear wheels and apply hand brake.
2. Push voltmeter or test lamp positive probe into yellow wire terminal at control unit connector. Connect negative probe to a suitable ground.
3. Start engine, then place selector lever in second gear or No. 2 position.
4. Accelerate slowly and observe voltmeter. Voltmeter should show no voltage below approximately 11 mph and battery voltage above approximately 16 mph.
5. If voltage is present above approximately 16 mph and no voltage below approximately 11 mph, speed sensor is satisfactory. If voltage is not present during test, check for faulty electrical connection, fuse or faulty speed sensor. Repair or replace as necessary. If voltmeter readings do not correspond with mph ranges, replace speed sensor.