Raising the Vehicle

Fig. 6 Height sensor operational test:

When weight is added to the rear of the vehicle, the body is forced downward which has the effect of rotating the height sensor actuating arm upward. This causes the height sensor to electrically start the internal time delay circuit. When the time delay has occurred, the sensor completes the compressor relay circuit to ground. With the relay energized, the 12 volt circuit to the compressor is completed and the compressor runs, causing the shock absorbers to inflate.
As the air shocks inflate, the body moves upward and starts rotating the height sensor actuating arm back toward the position the arm had prior to the weight addition.. When the body reaches the original trim height within 3-4 inch, the sensor opens the compressor relay circuit shutting off the compressor.