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Compressor Controls

The Powertrain Control Module (PCM) and Body Function Controller (BFC) share hardware and software for control of the AC Compressor Clutch. The Powertrain Control Module (PCM) and the Body Function Controller (BFC) communicate this information over the serial data Class 2 line.

The Body Function Controller (BFC) performs the following software functions:
^ Limit Low Speed Compressor Operation
^ Prevent Clutch Slippage
^ High Coolant Temperature
^ Monitor for Overpressure
^ Determine Low Ambient Pressure
^ Control Compressor Clutch

The Powertrain Control Module (PCM) performs the following functions:
^ Prevent Compressor Overspeed
^ Limit Compressor Speed (in PARK or NEUTRAL)
^ Drive Compressor Clutch
^ Perform Anti-Slug (Slugging is when a mass of liquid enters the AC Compressor Pump)