Compressor HVAC: Description and Operation

GF54.30-P-2015A K1 And K2 Line, Location/Purpose

The K1 and K2 line connects the instrument cluster to the automatic air conditioning pushbutton control module.

The serial data line K1 supplies the air conditioning control module with the following information from the instrument cluster:
- Outside temperature
- Engine coolant temperature
- Driving speed of vehicle
- Terminal 58d (illumination)
- Engine speed
- degree F / degree C conversion
- Full load fuel shutoff (diesel-engined models)
- Acceleration recognition (gasoline-engined model)

As of 02.97 also:
- Compressor emergency stop
- Compressor shutoff when accelerating

The serial data line K2 supplies the air conditioning control module with the following information from the instrument cluster:
- Refrigerant pressure
- Idle speed increase