Dual-Zone Mode

Vehicles with dual-zone climate controls will have an additional air temperature actuator. The Heater Ventilation Air Conditioning (HVAC) control module will have dual sliding temperature switches instead of the rotary temperature switch.

When a desired temperature setting is selected, a variable resistor is used to determine temperature door position signal value. The resistor changes the 12-volt signal coming into actuator and varies the voltage to move actuator into the proper position, based on the signal from HVAC control module. The motor opens right air temperature actuator to a position to divert sufficient air past the heater core to achieve the desired vehicle temperature. When the air temperature actuator sees an open in the control circuit, the actuator defaults to 6 volts and positions air temperature door mid-range.

The dual-zone climate controls allows for maximum temperature offset between driver and passenger. It is possible to select maximum airflow over evaporator core with one dual-zone switch, along with maximum airflow over heater core with the other dual-zone switch. Each air temperature actuator is independent from the other.