GM Service Manual Online
For 1990-2009 cars only

The heating, cooling, and ventilation for the vehicle can be controlled with this system. If your vehicle has the remote start feature, the climate control system functions as part of the remote start feature. See Remote Keyless Entry (RKE) System Operation .


Object Number: 1760990  Size: B2

Operation

Temperature Control: Turn the center knob clockwise or counterclockwise to increase or decrease the temperature inside the vehicle.

(Fan): Turn the left knob clockwise or counterclockwise to increase or decrease the fan speed. In any setting other than off, the fan will run continuously with the ignition on. To turn off the air completely, turn the fan to 0 and select the recirculation button.

Use the right knob to select from the following modes:

There is one position between each mode to finely adjust airflow position.

(Vent): This mode directs air to the instrument panel outlets.

(Bi-Level): This mode splits the air between the instrument panel outlets and the floor outlets.

(Floor): This mode directs most of the air to the floor outlets with some air directed to the windshield and side windows.

The right knob may also be used to select the defrost and defog modes that are described in this section.

You can also select modes by using the following buttons:

(Outside Air): Press this button to turn the outside air mode on. When this mode is on, outside air will circulate throughout the vehicle. When the button is pressed, an indicator light in the button comes on to show that it is activated. The outside air mode can be used with all modes, but it cannot be used with the recirculation mode.

(Recirculation): Press this button on the center knob to recirculate cabin air through the vehicle. It can be used to prevent outside air and odors from entering the vehicle or to help heat or cool the air inside the vehicle more quickly. An indicator light above the symbol will come on in this mode. Operation in this mode during periods of high humidity and cool outside temperatures may result in increased window fogging. If window fogging is experienced, select the defrost mode.

(Air Conditioning): Press this button to turn the air conditioning system on or off. When this button is pressed, an indicator light on the button comes on to show that the air conditioning is activated. The air conditioning can be selected in any mode as long as the fan switch is on.

On hot days, open the windows to let hot inside air escape; then close them. This helps to reduce the time it takes for the vehicle to cool down. It also helps the system to operate more efficiently.

For quick cool down on hot days, select the following settings:

  1. Vent mode.
  2. Outside air.
  3. Air conditioning.
  4. The coolest temperature.
  5. The highest fan speed.
  6. Once the vehicle's interior temperature is below the outside temperature, select recirculation mode for enhanced cooling.

Using these settings together for long periods of time may cause the air inside of the vehicle to become too dry. To prevent this from happening, after the air inside of the vehicle has cooled, turn the recirculation mode off.

The air conditioning system removes moisture from the air, so a small amount of water may drip underneath the vehicle while idling or after turning off the engine. This is normal.

(Heated Seats): If your vehicle has heated seats, see Heated Seats .

Defogging and Defrosting

Fog or frost on the inside of windows is a result of high humidity (moisture) condensing on the cool window glass. This can be minimized if the climate control system is used properly. To avoid fogging windows on rainy and humid days at temperatures above freezing, turn on the air conditioning system. Also, it is best to avoid the use of the recirculation mode, except when maximum A/C performance is needed or for short times to avoid exterior odors.

Use the defog mode to clear the windows of fog or moisture and warm the passengers. Use the defrost mode to remove fog or frost from the windshield more quickly. When you select either of these modes, or the floor mode which also helps defog the windows slightly, the system runs the air conditioning compressor and cancels recirculation mode to dry the air; however, the recirculation light will stay on. For best results, clear all snow and ice from the windshield before defrosting.

Turn the right knob to select the defog or defrost mode.

(Defog): This mode directs half of the air to the windshield and the side window outlets, and half to the floor outlets.

(Defrost): This mode directs most of the air to the windshield and the side window outlets, with some air directed to the floor outlets.

Rear Window Defogger

The rear window defogger uses a warming grid to remove fog from the rear window.

The rear window defogger will only work when the ignition is in RUN.

(Rear): Press this button to turn the rear window defogger on or off. An indicator light on the button comes on to show that the rear window defogger is activated.

The rear window defogger only works when the ignition is in RUN. The rear window defogger stays on for about 10 minutes after the button is pressed, unless the ignition is turned to ACC or LOCK. If turned on again, the defogger only runs for about five minutes before turning off. The defogger can also be turned off by pressing the button again or by turning off the engine.

If your vehicle has the remote start feature, the rear defogger automatically turns on if it is cold outside. When the vehicle transitions out of the remote start mode, the rear defogger will turn off. See Remote Keyless Entry (RKE) System Operation .

Notice: Do not use anything sharp on the inside of the rear window. If you do, you could cut or damage the warming grid, and the repairs would not be covered by the vehicle warranty. Do not attach a temporary vehicle license, tape, a decal or anything similar to the defogger grid.

Remote Start Climate Control Operation

If your vehicle has the remote start feature and it is activated, the climate control system heats and cools the inside of the vehicle using the modes that were set before the vehicle was turned off and the rear defogger automatically turns on. If your vehicle has heated seats, they may turn on if it is cold outside and will shut off when the key is turned to RUN. See Heated Seats .