K1 and K2 Line

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

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
"F"/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