HVAC Parameters

NOTE: These parameters indicate Powertrain Control Module (PCM) commands to, and signals from, various actuators and sensors in the HVAC systems.

AIR CONDITIONING SWITCH
A/C SWITCH - XXX RANGE: ON - OFF

This discrete parameter should be ON when the air conditioning switch is on and all other in-series switches are closed. It should be OFF when any sense switch in the air conditioning circuit is open.

AIR CONDITIONING CLUTCH
A/C CLUTCH RANGE: ON - OFF

This discrete parameter indicates that the PCM has energized the relay to engage the air conditioning compressor clutch. This parameter indicates that the PCM command has been given. It is not a feedback signal to indicate that the A/C clutch has actually engaged.

AIR CONDITIONING REQUEST SIGNAL
A/C REQUEST - XXX RANGE: ON - OFF

This discrete parameter on indicates the status of the PCM command to the air conditioning compressor. This is the actual computer command, not the switch position. A/C SWITCH indicates the position of the instrument panel switch.