Electronic Automatic Temperature Control: Notes

The dual-zone electronic automatic temperature control (EATC) module analyzes input from the following major sources:

• Temperature, airflow mode, blower, A/C and RECIRC selection (made by the vehicle occupants)
• In-vehicle temperature sensor
• Ambient temperature sensor
• Solar radiation sensor
• Evaporator temperature sensor
• Vehicle speed
• Engine coolant temperature

Using these inputs, the dual-zone EATC module determines the correct conditions for the following outputs:

• A/C compressor operation
• Blower speed
• Temperature blend door position
• Airflow mode door position
• Air inlet door position