2004 GMC ENVOY XL air condition

When Should an Air Bag Inate?
The driver’s and right front passenger’s frontal air bags
are designed to inate in moderate to severe frontal
or near-frontal crashes. But they are designed to inate
only if the impact speed is above the system’s
designed “threshold level.”
In addition, your vehicle has “dual stage” frontal air bags,
which adjust the amount of restraint according to crash
severity. For moderate frontal impacts, these air bags
inate at a level less than full deployment. For more
severe frontal impacts, full deployment occurs. If the front
of your vehicle goes straight into a wall that doesn’t move
or deform, the threshold level for the reduced deployment
is about 12 to 16 mph (19 to 26 km/h), and the threshold
level for a full deployment is about 16 to 25 mph
(26 to 40 km/h). The threshold level can vary, however,
with specic vehicle design, so that it can be somewhat
above or below this range.
If your vehicle strikes something that will move or
deform, such as a parked car, the threshold level will be
higher. The driver’s and right front passenger’s frontal
air bags are not designed to inate in rollovers, rear
impacts, or in many side impacts because ination
would not help the occupant.Your vehicle may or may not have a side impact air
bag. See Air Bag Systems in the Index. Side impact air
bags are designed to inate in moderate to severe
side crashes. A side impact air bag will inate if
the crash severity is above the system’s designed
“threshold level.” The threshold level can vary with
specic vehicle design. Side impact air bags are
not designed to inate in frontal or near-frontal impacts,
rollovers or rear impacts, because ination would not
help the occupant. A side impact air bag will only deploy
on the side of the vehicle that is struck.
In any particular crash, no one can say whether an air
bag should have inated simply because of the damage
to a vehicle or because of what the repair costs were.
For frontal air bags, ination is determined by the angle
of the impact and how quickly the vehicle slows down
in frontal and near-frontal impacts. For side impact
air bags, ination is determined by the location
and severity of the impact.
The air bag system is designed to work properly under
a wide range of conditions, including off-road usage.
Observe safe driving speeds, especially on rough
terrain. As always, wear your safety belt. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-16for tips on off-road driving.
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OnStar®System
Your vehicle may have this feature. OnStar®uses
global positioning system (GPS) satellite technology,
wireless communications, and state of the art call
centers to provide you with a wide range of safety,
security, information and convenience services.
A complete OnStar
®user’s guide and the terms and
conditions of the OnStar®Subscription Service
Agreement are included in your OnStar®-equipped
vehicle’s glove box literature. For more information, visit
www.onstar.com, contact OnStar
®at 1-888-4-ONSTAR
(1-888-466-7827), or press the blue OnStar®button
to speak to an OnStar®advisor 24 hours a day,
7 days a week.A completed Subscription Service Agreement is required
prior to delivery of OnStar
®services and prepaid
calling minutes are also required for OnStar®Personal
Calling and OnStar®Virtual Advisor use. Terms and
conditions of the Subscription Service Agreement can be
found at www.onstar.com.
OnStar®Services
One of the following plans is normally included for a
specic duration with each vehicle equipped with
OnStar
®. You can upgrade or extend your OnStar®
service plan to meet your needs.
Safe and Sound Plan

Automatic Notication of Air Bag Deployment
Emergency Services
Roadside Assistance
Stolen Vehicle Assistance
AccidentAssist
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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 will still enter the
vehicle, and will be 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.
h(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. Recirculation mode shuts
off when the engine is turned off.
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Temperature Control
Driver’s Side: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: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 equipped, 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 your 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
Your vehicle may have this feature. The lines you see
on the rear window warm the glass.
<(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 is equipped with heated mirrors, this
button will activate them.
Notice:Don’t use anything sharp on the inside
of the rear window. If you do, you could cut
or damage the warming grid, and the repairs
wouldn’t be covered by your warranty. Do not
attach a temporary vehicle license, tape, a decal
or anything similar to the defogger grid.
Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel to direct the airow.
Ventilation System
For mild outside temperatures when little heating or
cooling is needed, use the vent setting to direct outside
air through your vehicle.
Your vehicle’s ventilation system supplies outside air to
the inside of your vehicle when it is moving. With the
side windows closed, air will ow into the front air inlet
grilles, through the vehicle and out the air exhaust
valves.
Outside air will also enter the vehicle when the heater
or the air conditioning is running, unless you have
selected recirculation mode.
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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.
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 deectors, may affect the
performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
Dual Automatic Climate Control
System
Your vehicle may have the 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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Automatic Operation
AUTO (Automatic):When automatic operation is
active, the system will control the inside temperature,
the air delivery mode, 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 air conditioning
operation and air inlet mode will be automatically
controlled. The air conditioning compressor will run
when the outside temperature is over approximately
40°F (4°C). The air inlet will normally be set to
outside air. If it’s hot outside, the air inlet will
automatically switch to recirculate inside air to
help quickly cool down your vehicle.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 72°F (22°C)
temperature setting and allow about 20 minutes
for the system to regulate. Turn the driver’s or
passenger’s side temperature knob to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60°F (15°C), the system
will remain at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C),
the system will remain at the maximum heat setting.
Choosing either maximum setting may not cause
the vehicle to heat or cool any faster.
Manual Operation
To change the current setting, select one of the
following:
w9x(Fan):This button allows you to manually
adjust the fan speed. Press the up arrow to increase fan
speed and the down arrow to decrease fan speed.
The display will change to show you the selected fan
speed and the driver’s side temperature setting for ve
seconds.
(MODE):Press this button to manually change the
direction of the airow in your vehicle. Keep pressing the
button until the desired mode appears on the display.
The display will change to show you the selected
air delivery mode and the driver’s temperature setting
for ve seconds.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs approximately half
of the air to the instrument panel outlets, then directs 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 outlets and warmer
air to the oor outlets.
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6(Floor):This mode directs most of the air to the
oor outlets. Some air also comes out of the defroster
and side window outlets. The recirculation button cannot
be selected in oor mode.
h(Recirculation):Press this button to turn
recirculation mode on or off. When this button is
pressed, an indicator light in the button will also come
on to let you know that it is activated. Recirculation
mode is used to recirculate the air inside of your vehicle.
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. Recirculation
mode can be used with vent and bi-level modes, but it
cannot be used with oor, defog or defrost modes.
If the weather is cold and damp, the system may cause
the windows to fog while using recirculation mode. If the
windows do start to fog, select defog or defrost mode.
#A/C (Air Conditioning):Press this button to
manually turn the air conditioning system on or off.
When the system is on, the system will automatically
begin to cool and dehumidify the air inside of your
vehicle.
If you select air conditioning off while in front defrost or
defog mode, the air conditioning off symbol will ash
to let you know this option is not allowed.
You may notice a slight change in engine performance
when the air-conditioning compressor shuts off and
turns on again. This is normal.
A/C OFF (Air Conditioning Off):When you turn the
air conditioning off, the words A/C OFF will appear
on the display. When the air conditioning is selected or
in AUTO mode, the system will run the air conditioning
automatically.
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