Normal Operation
WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
The air suspension height sensor sends a voltage signal to the air suspension module. The output ranges from approximately 4.75 volts at minimum height (when the vehicle is low or in full jounce) to 0.25 volts at maximum height (when the vehicle is high or in full rebound).
When the air suspension height sensor indicates that the rear of the vehicle is lower than trim height under normal driving conditions, the air compressor will turn on and pump compressed air into the air springs. When the sensor indicates that the rear of the vehicle is raised above trim under normal driving conditions, this will cause the air to be vented from the air springs to lower the vehicle back to its trim height level.