2003 GMC Envoy Owner's Manual - Page 148

Operation Tips Keep the hood and front air inlets free of ice, snow, or any other obstruction (such as leaves). The heater and defroster will work far better, reducing the chance of fogging the inside of your windows. When you enter a vehicle in cold weather, turn the fan knob all the way to the right for a few moments before driving. This helps clear the intake ducts of snow and moisture, and reduces the chance of fogging the inside of your window. e Dual Automatic Climate Control System Your vehicle may have the optional dual automatic climate control system. With this system you can control the heating, cooling and ventilation for your vehicle. Keep the air path under the front seats clear of objects. This helps air to circulate throughout your vehicle. Adding outside equipment to the front of your vehicle, such as hood-air deflectors, may affect the performance of the heating and air conditioning system. Check with your dealer before adding equipment to the outside of your vehicle. When your vehicle is first started, the display will show the driver's temperature setting and air delivery mode for five seconds. Then it will show the outside temperature. Press this button to turn off the entire climate control system. Outside air will still enter the vehicle, and will be directed to the floor. Press the AUTO button, the mode button, the fan arrows, or either temperature knob to turn the system on. 0(Off): 3-23