Compressor/Pump: Description and Operation

Air Compressor Description
The air compressor is a positive displacement air pump, powered by a 12 volt DC permanent-magnet motor. The air compressor head contains intake and exhaust ports plus a solenoid-operated exhaust valve that releases air from the ALC system when energized. Air compressor intake air is drawn through an intake air hose and filter, mounted in the right side body rail. The air compressor is a serviceable part and is mounted on a bracket. The bracket is mounted to the underbody, right side, rear of the rear suspension.

Air Compressor Head Relief Sequence
In order to reduce current draw during air compressor starting, the position sensor performs an air compressor head relief sequence before air compressor operation. This sequence reduces the air pressure in the air compressor cylinder during start-up. The air compressor head relief sequence occurs as follows:
1. The exhaust solenoid is energized by the position sensor.
2. The air compressor is activated 1.3 seconds after the exhaust solenoid is energized.
3. The exhaust solenoid is de-energized 0.5 seconds after the air compressor is activated.