2008 GMC ENVOY air conditioning

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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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 outlet mode will be automatically
controlled. The air conditioning compressor will
run continuously 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 adjust. 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.
C(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.
@(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. Defog and defrost modes are described
later in this section.
If recirculation mode is selected with oor, defog, or
defrost modes, the indicator will ash three times and
then turn off indicating the selection is not available.
You may also notice that the air conditioning compressor
will run while in recirculation mode. This is normal and will
help to prevent fogging.
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 and
increase fan speed.
Recirculation mode, if selected, will be cleared when the
engine is turned off.
#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. The air conditioning symbol will appear on the
display when the air conditioning is on and will turn
off when the air conditioning is off.
If you turn the air conditioning off while in front defrost
or defog mode, the air conditioning symbol will turn
off, however, the A/C compressor will remain on to help
de-humidify the air inside the vehicle. If one of the
other modes is selected the compressor will then turn
the A/C off until it is selected again or the AUTO button
is pressed.
To avoid fogging the inside glass on rainy and humid
days at a temperature above freezing, press the air
conditioning button to run the A/C compressor. Also it is
best to avoid the use of the recirculation mode except
when maximum air conditioning performance is needed
or for short times to avoid exterior odors.
You may notice a slight change in engine performance
when the air-conditioning compressor shuts off and turns
on again. This is normal.
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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.
3-27

Tire Terminology and Denitions
Air Pressure:The amount of air inside the tire
pressing outward on each square inch of the tire.
Air pressure is expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of a tire’s height
to its width.
Belt
:A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead
:The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.Cold Tire Pressure
:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat
from driving. SeeInflation - Tire Pressure on
page 5-64.
Curb Weight
:The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant, but
without passengers and cargo.
DOT Markings
:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight Rating.
SeeLoading Your Vehicle on page 4-34.
GAWR FRT
:Gross Axle Weight Rating for
the front axle. SeeLoading Your Vehicle on
page 4-34.
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Fuses Usage
5 Driver Side High-Beam Headlamp
6 Driver Side Low-Beam Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
15 Electric Adjustable Pedals
16 Truck Body Controller, Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
20 Cooling Fan
21 Horn
22 Ignition EFuses Usage
23 Electronic Throttle Control
24Instrument Panel Cluster, Driver
Information Center
25Automatic Shift Lock Control
System
26Transmission Control Module
Canister
27 Backup
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Antilock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Blower
50 Passenger Side Trailer Turn
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Fuses Usage
51 Driver Side Trailer Turn
52 Hazard Flashers
53 Headlamp Driver Module
54Air Injection Reactor (AIR)
Solenoid
56 Air Injection Reactor (AIR) Pump
58Vehicle Stability Enhancement
System (StabiliTrak
®)
59 Regulated Voltage Control
Relays Usage
37 Headlamp Wiper
38 Rear Window Wiper/Washer
39 Fog Lamps
40 Horn
Relays Usage
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
45 Cooling Fan
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
55 Air Injection Reactor (AIR) Solenoid
57 Powertrain
Miscellaneous Usage
48 Instrument Panel Battery
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