Dual Zone Climate Control
Temperature SettingsWith the system in any mode and temperature between 19°C and 29°C (66°F and 84°F), turning the temp knob in either direction, or pressing the warm or cold button, increases or decreases temperature one degree. If the knob is turned in the decrease direction or cool button is pressed to achieve the lowest setting. with the set temperature of 18°C (65°F), temperature drops immediately to 16°C (60°F). If the knob is turned in the increase direction or the warm button is pressed to achieve the highest setting with a set temperature of 29°C (85°F), the set temperature will jump immediately to 32°C (90°F).
An increase or decrease of the set temperature signals the heater and A/C programmer to take the steps necessary (change blower speed, change air discharge location, change discharge temperature) to bring the passenger compartment temperature to the new temperature setting.
NOTICE: The compressor does not nun in the OFF or ECON setting therefore cooling the interior of the vehicle beyond the ambient air temperature is not possible in OFF or ECON settings.
OFF Setting
With this setting selected, the blower motor or A/C compressor will not operate. However, the system will still try to reach the temperature ran(2e selected. For example, if 21°C (70°F) is selected and it is a cold day, the car may eventually reach the 21°C (70°F) temperature range, but the increase may take an extended period of time because the blower fan is not operating. If it is a hot day, the blower can only cool the car to near ambient air temperature since in this position the blower motor and A/C compressor will not nun. This selection forces the air inlet valve open to ambient air and sends half of the air out of the floor ducts and half of the air Out of the defroster outlets.
The OFF mode does not affect the rear defog, ambient temperature, and set temperature. If the manual RECIRC mode has been previously activated, the OFF key will cause the RECIRC mode door to return to the automatic control.
ECON Setting
In this setting, the system will not allow the A/C compressor to operate. Thus the system cannot cool the vehicle to a temperature any colder than the ambient air temperature. This setting automatically determines blower speed and air outlet positions based on different inputs. All incoming air into the HVAC module is from the outside. Depending on the heating or cooling requirement, most of the air will enter the passenger compartment from one of the following positions:
^ Out the floor heater outlet, rear outlets.
^ Out the A/C outlets, rear outlets.
^ A/C, heater and rear outlets.
AUTO Setting
In this setting everything is controlled automatically based on the various A/C system inputs. In this setting, the system has the capability of any fan blower speed, any air inlet position, and any air outlet position to attain and maintain the selected temperature. At temperatures above 4°C (40°F), the compressor is enabled to dehumidify the air entering the passenger compartment. Depending on the heating or cooling requirements, most of the air will enter the passenger compartment from one of the following positions:
^ Out the floor heater outlet, rear outlets.
^ Out the A/C outlets, rear outlets.
^ Out the A/C, heater and rear outlets.
DEFOG Setting
This setting splits the air flow between the defroster and floor ducts. At temperatures above 4°C (40°F), the compressor is enabled to dehumidify the air entering the passenger compartment.
DEFROST Setting
In this setting, everything is controlled automatically, as in AUTO except that most of the air is delivered out of the defroster grille on the top of the instrument panel. At temperatures above 4°C (40°F), the compressor is enabled to dehumidify the air entering the passenger compartment.
DUAL ZONE Setting
The dual zone is activated by pressing the center of the passenger temperature control button or by pressing either the top or bottom arrow. On some vehicles the dual zone feature can be activated by adjusting the passenger climate control knob located on the right front door.
The dual zone A/C system is a vacuum and electronically controlled heating, ventilating and air conditioning system. Both electronic and vacuum circuits determine air intake and discharge locations. Electronic circuits also control mode, A/C compressor clutch operation, fan operation and discharge air temperature.
In the dual zone system, the air mix valve is split in half and each half has its own actuator.
When the system is operating in dual zone mode, the heater and A/C programmer operates each actuator separately. Driver side discharge temperature is dependent upon:
^ Coolant temperature.
^ Ambient temperature.
^ Inside temperature.
^ Sun load sensor.
^ Heater and A/C control SET temperature.
Passenger side discharge air temperature is dependent upon:
^ Coolant temperature.
^ Ambient air temperature.
^ Inside air temperature.
^ Sun load sensor.
^ Passenger temperature control setting information.
When the system is operating in any mode but dual zone mode, the actuators are operating in unison as the system works to maintain the heater and A/C control SET temperature.
RECIRC Setting
When the RECIRC button is pressed the LED will illuminate. The RECIRC switch sends a message to the programmer which causes air to be recirculated through the HVAC system from the passenger compartment.
When RECIRC mode is selected, the programmer allows vacuum to be applied to the air inlet valve actuator which positions the air inlet valve in the recirculate position.
RECIRC mode is available for operation in UPPER, LOWER and BI-LEVEL modes. RECIRC is not allowed during DEFROST and DEFOG modes as this could cause windshield fogging.
While RECIRC is operational, any ignition cycle will cancel the function, and allow outside air into the system.
The manual RECIRC will remain activated until one of the following occurs:
^ The RECIRC button is pressed a second time.
^ The front defrost mode is selected.
^ The DEFOG mode is selected.
^ The AUTO button is pressed.
^ The OFF button is pressed.