Purpose of K lines troubleshooting chart IC - AD54.30-P-5000-04A

Purpose of K lines 

The air conditioning pushbutton unit receives the following data from the instrument cluster via the serial data bus K1 : 

• Outside temperature
• Engine coolant temperature
• Driving speed
• Terminal 58d (illumination)
• Engine speed
• °F/°C changeover
• Full-load shut-off (diesel)
• Acceleration recognition (gasoline-engined vehicle)
• A/C compressor emergency off (from engine control module to IC via CAN)
• Switch off A/C compressor when accelerating (from engine control module to IC via CAN)

The instrument cluster receives the following data from the air conditioning pushbutton unit via the serial data bus K2 : 

• A/C pressure
• Idle speed increase