Operation CHARM: Car repair manuals for everyone.

A/C Compressor Control

The Powertrain Control Module (PCM) and the BCM share hardware and software for control of the NC Compressor Clutch. The PCM and the BCM communicate this information over the serial data class 2 line.

The BCM performs the following software functions:
^ Limits low speed compressor operation
^ Prevents clutch slippage
^ High coolant temperature
^ Monitors for overpressure
^ Determines low ambient pressure
^ Controls the compressor clutch

The PCM performs the following functions:
^ Prevents compressor overspeed
^ Limits compressor speed (in PARK or NEUTRAL)
^ Drives the compressor clutch
^ Performs anti-slug

Slugging is when a mass of liquid enters the A/C compressor pump