Dual Zone

The Dual Zone Heating and Air Conditioning system allows completely independent side-to-side temperature control of the discharge air.

The Dual Zone Heating and Air Conditioning system includes a dust and odor air filter. The filter element is the same size as the air conditioning evaporator to ensure ample capacity. A door at the base of the heating and air conditioning housing below the glove box provides easy access to the filter element.

FRONT CONTROL PANEL
The instrument panel mounted control and integral computer contains:
- a power button which allows the system to be completely turned off. The display shows only the outside temperature when the system is off
- a dual zone button which allows the selection of either single (driver) or dual (driver and passenger) temperature control.
- two temperature set buttons for completely independent side-to-side temperature control of the discharged air. The full range of temperature that the system can produce in any mode is available on either side of the vehicle by independently adjusting the controls.
- auto high and auto low buttons which allow various modes of automatic temperature control operation. Contains an LED that illuminates to show when the function is operational.
- a rear control button to allow selection of rear fan control modes.
- a outside temperature button that allows the operator to select either outside air or passenger set temperatures.
- a manual fan button that allows the operator to manually select six different fan speeds.
- a manual mode button which allows the operator to manually select the air delivery mode.
- an air conditioning on/off switch. The Snowflake button contains an LED that illuminates to shown when the function is in operation.
- air recirculation on/off switch. The Recirculate button contains an LED
- separate front rear window defogger on/off switches. Contains an LED that illuminates to show when the function is operational.
- rear fan button to allow the driver to set rear blower speed to AUTO for automatic speed adjustment, or REAR to give control to the intermediate seat occupants, or OFF to shut the rear blower down.

Computer logic remembers the settings of the controls when the ignition is turned off and retains those settings after a restart, etc.

The computer logic provides variable air recirculation under high temperature and humidity conditions. Because recirculation is generally accompanied to outside air gradually approaches full recirculation over a broad temperature range.

REAR CONTROL PANEL
Primary control of the rear compartment unit is on the instrument panel. This control allows the driver to set the rear compartment fan speed, to turn the rear unit off, or to give control to the intermediate seat occupants by switching the REAR position. When the rear unit is controlled from the instrument panel, rear blower speed is automatically controlled based on the front control's temperature setting. Air flow through the floor console is directed through upper or lower outlets based on the front mode settings.

A rear rotary blower switch is centrally mounted on the center floor console between the second row seats allows fan speed control of the rear unit by intermediate seat passengers.

The Dual Zone Automatic Temperature Control (ATC) System automatically maintains the interior comfort level desired by the driver and front seat passenger. This is accomplished by using two infrared sensors located in the center of the instrument panel. The two infrared sensors independently measure the surface temperature of the driver and front seat passenger. Based on the sensor input, the system automatically adjusts the air temperature, the airflow volume, the airflow distribution, and amount of inside air recirculation to maintain front seat occupant comfort, even under changing outside weather conditions.

When DUAL is displayed in the ATC control unit, the driver and passenger air outlet temperatures can be individually adjusted from the two independent TEMP buttons. When a front seat passenger is not present, pressing the DUAL button will disable the passenger's infrared sensor and control the entire system based only on the driver's temperature setting. The outside temperature will replace the passenger's temperature setting in the display. Pressing the DUAL button a second time or adjusting the passenger's TEMP button will reactivate the passenger's infrared sensor and return the system to dual independent temperature operation.

This system offers several manual override features. The indicator light in both the AUTO HI or AUTO LO buttons will turn off when the system is
being used in the manual mode. The fan speed, airflow distribution, and outside air/recirculated air can be manually adjusted.

The front blower control can be set to any fixed blower speed by pressing the rocker switch up or down. This allows the front occupants to control the volume of air circulated in the vehicle and cancel the auto mode. The fan will now operate at a fixed speed until additional speeds are selected or until either the AUTO HI or AUTO LO buttons are pressed. The system will continue to automatically adjust air temperature and airflow distribution.

When the outside air contains smoke, odors, high humidity, or if rapid cooling is desired, interior air can be recirculated by pressing the recirculation button. The recirculate symbol will illuminate in the display when this button is selected.
- The system automatically adjusts the temperature, mode and fan speed.
- When the ATC System is off, the recirculation door is automatically closed to prevent outside air from entering the passenger compartment.
- Air conditioning is available in any mode by pressing the snowflake, A/C on/off, button.

To provide maximum comfort in the automatic mode during cold start-ups, the blower fan will remain off and DELAY will appear in the display until the engine warms up. The estimated the time remaining until the DELAY is complete will appear periodically in the display. However, the fan will engage immediately if the defrost mode is selected or by pushing the blower switch and manually adjusting the fan speed.