GMC Sierra Owners Manual
Dual Automatic Climate Control System
The heating, cooling, and ventilation in the vehicle can be controlled with this system. The vehicle also has a flow-through ventilation system described later in this section.
A. Driver and Passenger Temperature Controls
F. Outside Air
G. Air Delivery Mode Control
J. Rear Window Defogger
K. Air Conditioning
L. PASS (Passenger)
(On/Off): Press to turn the climate control system on or off.
Outside air still enters the vehicle, and is directed to the floor. This direction can be changed by pressing the mode button.
Recirculation can be selected once you have selected vent or bi-level mode. The temperature can also be adjusted using either temperature button. If the air delivery mode or temperature settings are adjusted with the system off, the display illuminates briefly to show the settings and then returns to off. The system can be turned back on by pressing either ,
Driver and Passenger Side Temperature Controls
The driver and passenger side temperature buttons are used to adjust the temperature of the air coming through the system on the driver or passenger side of the vehicle. The temperature can be adjusted even if the system is turned off. This is possible since outside air always flows through the system as the vehicle is moving forward unless it is set to recirculation mode. See “Recirculation” later in this section.
Press the + or − buttons to increase or decrease the cabin temperature.
The driver side or passenger side temperature display shows the temperature setting increasing or decreasing.
The passenger temperature setting can be set to match the driver temperature setting by pressing the PASS button and turning off the PASS indicator. When the passenger temperature setting is set different than the driver setting, the indicator on the PASS button illuminates and both the driver side and passenger side temperature displays are shown.
When in defrost mode the passenger temperature setting cannot be changed.
AUTO (Automatic): When automatic operation is active, the system controls the inside temperature, the air delivery, and the fan speed.
Use the steps below to place the entire system in automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display changes to show the current temperature(s) and AUTO is lit on the display. The current air delivery mode and fan speed are also displayed for about five seconds.
When AUTO is selected, the air conditioning operation and air inlet are automatically controlled.
The air conditioning compressor may run when the outside temperature is above freezing.
The air inlet will normally be set to outside air. If it is hot outside, the air inlet may automatically switch to the recirculate mode to help quickly cool down the air inside the vehicle. The light on the button comes on in recirculation.
2. Set the driver and passenger temperature.
To find your comfort setting, start with a 23°C (74°F) temperature setting and allow about 20 minutes for the system to regulate. Use the driver or passenger temperature buttons to adjust the temperature setting as necessary. If a temperature setting of 15°C (60°F) is chosen, the system remains at the maximum cooling setting. If a temperature setting of 32°C (90°F) is chosen, the system remains at the maximum heat setting. Choosing either maximum setting will not cause the vehicle to heat or cool any faster.
Do not cover the solar sensor located on the top of the instrument panel near the windshield. This sensor regulates air temperature based on sun load. For more information on the solar sensor, see “Sensors” later in this section.
To avoid blowing cold air in cold weather, the system delays turning the fan on until warm air is available. The length of delay depends on the engine coolant temperature. Pressing the fan switch overrides this delay and changes the fan to a selected speed.
(Fan Control): Press these buttons to increase or decrease the fan speed.
Pressing either fan button while in automatic control places the fan under manual control. The fan setting remains displayed and the AUTO light turns off. The air delivery mode remains under automatic control.
(Air Delivery Mode Control):
Press these buttons to change the direction of the airflow in the vehicle.
Repeatedly press either button until the desired mode appears on the display.
Pressing either mode button while the system is off changes the air delivery mode without turning the system on.
Pressing either mode button while in automatic control places the mode under manual control. The air delivery mode setting displays and the AUTO light turns off. The fan remains under automatic control.
(Vent): Air is directed to the instrument panel outlets.
(Bi-Level): Air is divided between the instrument panel and floor outlets. Some air is directed toward the windshield and side window outlets.
(Floor): Air is directed to the floor outlets, with some to the windshield, side window outlets, and second row floor outlets. In this mode, the system automatically selects outside air.
(Defog): This mode clears the windows of fog or moisture. Air is directed to the windshield, floor outlets, and side window vents. In this mode, the system turns off recirculation and runs the air conditioning compressor unless the outside temperature is close to freezing. The recirculation mode cannot be selected while in the defrost mode.
(Defrost): This mode removes fog or frost from the windshield more quickly. Air is directed to the windshield and side window vents, with some directed to the floor vents. In this mode, the system automatically forces outside air into the vehicle and runs the air conditioning compressor unless the outside temperature is close to freezing. The recirculation mode cannot be selected while in the defrost mode.
The passenger temperature control cannot be activated while in defrost mode. If the PASS button is pressed, the button indicator flashes three times and will not work. If the passenger temperature buttons are adjusted, the driver temperature indicator changes. The passenger temperature will not be displayed.
If vent, bi-level, or floor mode is selected again, the climate control system displays the previous temperature settings.
Do not drive the vehicle until all windows are clear.
(Air Conditioning): Press to turn the air conditioning (A/C) compressor on and off. An indicator light comes on to show that the air conditioning is on.
If this button is pressed when the air conditioning compressor is unavailable due to outside conditions, the indicator flashes three times and then turns off. If the air conditioning is on and the outside temperature drops below a temperature which is too cool for air conditioning to be effective, the air conditioning light turns off to show that the air conditioning mode has been canceled.
On hot days, open the windows long enough to let hot inside air escape.
This helps to reduce the time it takes for the vehicle to cool down.
It also helps the system to operate more efficiently.
The air conditioning system removes moisture from the air, so a small amount of water might drip under the vehicle while idling or after turning off the engine. This is normal.
(Recirculation): Press to turn the recirculation mode on. An indicator light comes on to show that recirculation is on.
This mode recirculates and helps to quickly cool the air inside the vehicle. It can be used to help prevent outside air and odors from entering the vehicle.
The recirculation mode cannot be used with floor, defog, or defrost modes. If recirculation is selected with one of those modes, the indicator light flashes three times and then turns off. The air conditioning compressor also comes on when this mode is activated.
While in recirculation mode, the windows may fog when the weather is cold and damp. To clear the fog, select either the defog or defrost mode and increase the fan speed.
The recirculation mode can be turned off by pressing the outside air button, or by turning off the ignition.
(Outside Air): Press to turn the outside air mode on. An indicator light on the button comes on to show that outside is on. When selected, air from outside the vehicle circulates throughout the vehicle. The recirculation mode cannot be used with the outside air mode.
Rear Window Defogger
The rear window defogger uses a warming grid to remove fog from the rear window.
(Rear Window Defogger): For vehicles with this feature, press to turn the defogger on or off.
It automatically turns off several minutes after it has been activated.
The defogger can also be turned off by turning the engine off. Do not drive the vehicle until all windows are clear.
Notice: Do not use a razor blade or sharp object to clear the inside rear window. Do not adhere anything to the defogger grid lines in the rear glass. These actions may damage the rear defogger. Repairs would not be covered by your warranty.
Heated Mirror: For vehicles with heated outside rearview mirrors, the mirrors heat to help clear fog or frost from the surface of the mirror when the rear window defog button is pressed. See Power Mirrors on page 2‑15.
The solar sensor, located in the defrost grille in the middle of the instrument panel, monitors the solar heat. Do not cover the solar sensor or the system will not work properly.
The interior temperature sensor, located in the headliner, measures the temperature of the air inside the vehicle.
There is also an exterior temperature sensor located behind the front grille. This sensor reads the outside air temperature and helps maintain the temperature inside the vehicle. Any cover on the front of the vehicle could cause a false reading in the displayed temperature.
The climate control system uses the information from these sensors to maintain comfort settings by adjusting the outlet temperature, fan speed, and the air delivery mode.
The system may also supply cooler air to the side of the vehicle facing the sun. The recirculation mode will also be used as needed to maintain cool outlet temperatures.