The vehicle uses an HD-6 compressor. The HD-6 compressor is a 6-cylinder axial-type mechanism consisting of 3 double-ended pistons actuated by a swash plate shaft assembly. The compressor is located on the lower right of the engine centerline (right-front corner of the engine compartment). The compressor is belt-driven from the crankshaft pulley. The compressor performs the following 2 main functions:
| • | Provides pressure and temperature levels at which a heat exchange may take place in the condenser. |
| The low-pressure refrigerant vapor from the evaporator is compressed into a high-pressure, high-temperature vapor. |
| • | Pumps refrigerant and refrigerant oil through the A/C system. |
A magnetic clutch is used in order to engage the compressor shaft. When voltage is supplied to the clutch coil (2), the clutch plate and hub assembly, which is solidly coupled to the compressor shaft, is drawn by the magnetic force rearward toward the pulley. This pulley rotates freely on the front head casting. The magnetic force holds the clutch plate and the pulley together as 1 unit. The compressor shaft then turns with the pulley. When the powertrain control module (PCM) removes the voltage from the clutch coil, the springs in the clutch plate and hub assembly move the clutch plate away from the pulley. The clutch plate and the compressor shaft cease to rotate.
The compressor has a pressure relief valve (1) that opens and allows the refrigerant to vent off to the atmosphere when high-side pressure exceeds 3620 kPa (525 psi). This is done in order to prevent system damage. Correct any condition that causes this valve to open. Replace the refrigerant oil and the refrigerant as necessary.
