2008 GMC ENVOY climate control

Climate Controls
Dual Climate Control System
With this system you can control the heating, cooling,
and ventilation for your vehicle.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the
fan speed. If the knob is in off mode, outside air still
enters the vehicle, and is directed based on the position
of the mode knob. The temperature can still be adjusted
using the temperature knob.
Turn the right knob clockwise or counterclockwise to
direct the airow inside of your vehicle.To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs about half of the air
to the instrument panel outlets; then directs most of
the remaining air to the oor outlets. A little air is
directed toward the windshield and the side window
outlets. Cooler air is directed to the upper vents
and warmer air to the oor outlets.
6(Floor):This mode directs most of the air to the
oor outlets with a little air directed to the windshield
and the side window outlets. The recirculation button
cannot be selected while in oor mode.
@(Recirculation):Recirculation mode is used to
recirculate the air inside of your vehicle. When this button
is pressed, an indicator light in the button will come on
to let you know that it is active. Use this mode to help
prevent outside odors and/or dust from entering your
vehicle or to help cool the air inside of your vehicle more
quickly. The air conditioning compressor will also come
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 fan speed.
Defog and defrost modes are described later in this
section.
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Driver’s Side Temperature Lever:The lever on the
left side of the climate control panel is used to raise
or lower the temperature on the driver’s side of
the vehicle. Slide the lever up or down to adjust
the temperature.
Passenger’s Side Temperature Lever:The lever on
the right side of the climate control panel is used to raise
or lower the temperature on the passenger’s side of
the vehicle. Slide the lever up or down to adjust the
temperature. This lever also adjusts the temperature
to the rear seat outlets.
When the temperature outside is 0°F (−18°C) or lower,
use the engine coolant heater, if the vehicle has
one, to provide warmer air, faster to your vehicle.
#(Air Conditioning):Press this button to turn the
air-conditioning system on or off. When the button is
pressed, an indicator light will come on and the system
will begin to cool and dehumidify the air inside of the
vehicle. You may notice a slight change in engine
performance when the air conditioning compressor
shuts off and turns on again. This is normal.
Defogging and Defrosting
Fog 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. There are two modes to choose from to clear
fog or frost from your windshield. 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.
Turn the right knob clockwise or counterclockwise to
select one of the following modes:
-(Defog):This mode directs the air to the
oor outlets, windshield and side window outlets.
The recirculation button cannot be selected while in
defog mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window outlets, with only a little
air directed to the oor outlets. The air conditioning
compressor may run to dehumidify the air to prevent
window fogging. The recirculation button cannot be
selected while in defrost mode. Do not drive the vehicle
until all the windows are clear.
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Rear Window Defogger
If your vehicle has the rear window defogger a warming
grid is used to remove fog on the rear window.
<(Rear):Press this button to turn the rear window
defogger on or off. An indicator light in the button
will come on to let you know that the rear window
defogger is active. The rear window defogger will
automatically turn off approximately ten minutes
after the button is pressed.
If your vehicle has heated mirrors, this button will
activate them.
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 your warranty. Do not attach a temporary
vehicle license, tape, a decal or anything similar to
the defogger grid.
Dual Automatic Climate Control
System
With this system you can control the heating, cooling
and ventilation for your vehicle. When your vehicle
is rst started and the climate control system is on,
or if the climate control system has been turned on,
the display will show the driver’s temperature setting for
ve seconds. Then it will show the outside temperature.
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9(Off):Press this button to turn off the entire climate
control system. Outside air will still enter the vehicle, and
will be directed to the oor. Press the AUTO button, the
mode button, the fan arrows, or either temperature knob
to turn the system on.
C(Mode):Press this button to manually select the air
delivery mode to the oor, instrument panel, or windshield
outlets. The system will stay in the selected mode until
the mode button is pressed again or the AUTO button is
pressed.
Driver’s Side Temperature Knob:Turn this knob
clockwise or counterclockwise to raise or lower the
temperature on the driver’s side of the vehicle. The
display will show the temperature setting decreasing
or increasing and an arrow pointing toward the driver.
This knob can also adjust the passenger’s side
temperature setting if the two are linked.Passenger’s Side Temperature Knob:Turn this
knob clockwise or counterclockwise to manually raise or
lower the temperature on the passenger’s side of the
vehicle. The display will show the temperature setting
decreasing or increasing and an arrow pointing toward
the passenger. The passenger’s temperature setting
can be set to match and link to the driver’s temperature
setting by pressing and holding the AUTO button for
three seconds. When adjusting the driver’s side
temperature setting, the passenger’s side temperature
setting will follow and both arrows will appear on the
display. The passenger’s side temperature setting also
resets and relinks to the driver’s side temperature setting
if the vehicle has been off for more than three hours.
Outside Air Temperature Display
A new outside temperature reading will be displayed
if the vehicle has been off for more than three hours.
If the vehicle has been off for less than three hours,
the old temperature reading may be displayed because
underhood heat is affecting the true outside temperature.
Underhood heat can also affect the outside temperature
while the engine is running. It may also take
several minutes of driving before the display
updates to the actual outside temperature.
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Defogging and Defrosting
Fog on the inside of the windows is a result of moisture
condensing on the cool window glass. This can be
reduced if the climate control system is used properly.
You can use either defog or front defrost to clear
fog or frost from your windshield.
-(Defog):Use this setting to clear the windows of
fog or moisture. This setting will deliver air to the
oor and windshield outlets.
0(Front Defrost):Press the front defrost button to
clear the windshield and side windows of frost or fog
quickly. The system will automatically control the fan
speed if you select defrost from AUTO mode. If the
outside temperature is 40°F (4°C) or warmer, your air
conditioning compressor will automatically run to help
dehumidify the air and dry the windshield. Do not drive
the vehicle until all the windows are clear.
Rear Window Defogger
If your vehicle has the rear window defogger a warming
grid is used to remove fog from the rear window.
<(Rear):Press this button to turn the rear window
defogger on or off.
An indicator light in the button will come on to let you
know that the rear window defogger is activated.
The rear window defogger will turn off approximately
10 minutes after the button is pressed. If you need
additional warming time, press the button again.
If your vehicle has heated mirrors, they will come on
when this button is pressed.
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.
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Outlet Adjustment
Use the air outlets located in the center and on the
side of the instrument panel to direct the airow. Use
the thumbwheels near the air outlets to open or close
off the airow.
Operation Tips

Clear away any ice, snow, or leaves from air inlets
at the base of the windshield that could block the
ow of air into the vehicle.
Keep the path under the front seats clear of objects
to help circulate the air inside of the vehicle more
effectively.
Use of non-GM approved hood deectors can
adversely affect the performance of the system.
Check with your dealer/retailer before adding
equipment to the outside of your vehicle.
Rear Climate Control System
Your vehicle has one of the following rear climate
control systems. With either of these systems, the
rear climate controls will be disabled when the front
climate control system is in defrost. This occurs to
provide maximum airow to clear the windshield.The temperature of the air coming through the rear
outlets is determined by the front passenger temperature
setting. Use the mode knob to change the direction of
airow (upper, bi-level or oor) to the rear seat area.
PWR (Power):Press this button to turn the rear climate
controls on or off.
H(Panel):This position distributes air from the rear
console outlets.
)(Bi-level):This position distributes air from the
second seat side oor outlets and the rear console
outlets.
6(Floor):This position distributes air from the
second seat side oor outlets.
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If your vehicle has the rear seat audio system, the
lower buttons are used to adjust the rear seat climate
control system. The temperature of the air coming
through the rear outlets is determined by the front
passenger temperature setting.
P(On/Off):Press this button to turn the rear climate
controls on or off.
z9 y(Fan):Press this button to adjust the fan
speed.
z\y(Mode):Press this button to change the
direction of airow (panel, bi-level or oor) to the rear
seat area.
The rear control only turns on if the front climate control
system is on and not in defrost mode.
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Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can not
see or smell CO. It can cause unconsciousness
or death. SeeEngine Exhaust on page 2-37.
To maximize your safety when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main heating
or cooling system on and with the fan on
any speed. This will bring fresh, outside air
into your vehicle. Do not use the climate
control setting for maximum air because it
only recirculates the air inside your vehicle.
SeeDual Climate Control System on
page 3-21.Towing a trailer requires a certain amount of
experience. Before setting out for the open road, you’ll
want to get to know your rig. Acquaint yourself with the
feel of handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connection, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that
the load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
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