climate control CHEVROLET TAHOE 2003 2.G User Guide

Defogging and Defrosting
Fog on the inside of the 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 the side window vents. The air
conditioning compressor will run automatically to
dehumidify the air to prevent window fogging. The
recirculation mode cannot be selected while in the
defog mode.
1(Defrost):This mode directs most of the air to the
windshield and the side window vents, with only a
little air directed to the ¯oor vents. The air conditioning
compressor will run automatically to dehumidify the
air to prevent window fogging. The recirculation mode
cannot be selected while in defrost mode.
Do not drive the vehicle until all the windows are clear.
Rear Window Defogger
The lines you see on the rear window warm the glass.
The rear window defogger uses a warming grid 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 automatically turn off
several minutes after the button is pressed. Pressing the
button while the defogger is running can also turn off
the defogger.
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.
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Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle. Your vehicle also
has a ¯ow-through ventilation system described later in
this section.
You can select different climate control settings for the
driver and passengers.
Driver's Side Temperature Knob
The driver's side knob is used to adjust the temperature
of the air coming through the system on the driver's
side. The temperature can be adjusted even if the
system is turned off. This is possible since outside airwill always ¯ow through the system as the vehicle is
moving forward unless it is set to recirculation mode.
See ªRecirculationº later in this section.
Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the driver will be displayed under
and to the left of the temperature setting.
Passenger's Side Temperature Knob
The passenger's side knob can be used to change the
temperature of the air coming through the system on the
passenger's side of the vehicle. The temperature can be
adjusted even if the system is turned off. This is possible
since outside air will always ¯ow through the system as
the vehicle is moving forward unless it is set to
recirculation mode. See ªRecirculationº later in this
section.
Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the passenger will be displayed
under and to the right of the temperature setting.
The passenger's temperature setting can be set to
match the driver's temperature setting by pressing and
holding the AUTO button for four seconds. Both the
driver and passenger arrows will be displayed.
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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. This direction can be changed
by pressing the mode button. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
Manual Operation
You may manually adjust the air delivery mode or fan
speed.
w9x(Fan):The switch with the fan symbol allows
you to manually adjust the fan speed. Press the up
arrow to increase fan speed and the down arrow
to decrease fan speed.
Pressing this button when the system is off will turn the
system on.
C(Mode):Press this button to manually change the
direction of the air¯ow in your vehicle; keep pressing the
button until the desired mode appears on the display.
If you press the mode button to select an air delivery
mode, the display will change to show you the selected
air mode delivery. The display will then show the current
status of the system. When the system is turned off, the
display will go blank after displaying the current status of
the system.
H(Panel):This setting will deliver air to the
instrument panel outlets.
)(Bi-Level):This setting will deliver warmer air to the
¯oor and cooler air to the instrument panel outlets.
6(Floor):This setting will deliver air to the ¯oor
outlets.
-(Defog):See ªDefogging and Defrostingº later in
this section.
@(Recirculation):Press this button to limit the
amount of outside air entering your vehicle. The light on
the recirculation button will glow. This is helpful when you
are trying to limit odors entering your vehicle and for
maximum air conditioning performance in hot weather.
Press this button again to allow outside air to enter the
vehicle. The light on the recirculation button will go off.
Pressing this button also cancels the auto recirculation
feature. To resume the auto recirculation function, press
the AUTO button. Each time the vehicle is started, the
system will revert to the auto recirculation function.
If you select recirculation while in defrost, defog or ¯oor,
the light in the button will ¯ash and then go out to let you
know that this is not allowed. This is normal and helps to
prevent fogging.
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When the weather is cool or damp, operating the system
in recirculation for extended periods of time may cause
fogging of the vehicle's windows. To clear the fog, select
either defog or front defrost.
You may also notice that the A/C compressor will run
while in recirculation mode. This is normal and helps to
prevent fogging.
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. This direction can be changed
by pressing the mode button. The temperature can also
be adjusted using either temperature knob. Press the up
or down arrows on the fan switch, the defrost button, the
AUTO button, or the air conditioning button to turn the
system on when it is off.
Display
If you press the MODE button to select an air delivery
mode, the display will change to show you the selected
air delivery mode. After ten seconds, the display will
change to show the driver temperature setting and the
selected mode.
If you press the up or down arrows on the fan switch,
the display will change to show the selected fan speed.
After ten seconds, the display will change to show
the driver temperature setting and the selected mode.Whenever you press AUTO, the display will change to
show the following:
·the current driver's set temperature and an arrow
for ®ve seconds,
·the current passenger's set temperature setting and
an arrow for ®ve seconds and
·the automatic air delivery mode and fan speed.
If the driver's and passenger's temperature settings are
the same when AUTO is pressed, the temperature
setting and both arrows will be displayed for ®ve
seconds along with the automatic air delivery mode and
fan speed. After the ®ve second update, the display
will change to show the temperature setting, both arrows
and AUTO.
Air Conditioning
#
(Air Conditioning):Press this button to turn the air
conditioning (A/C) compressor on and off. The snow¯ake
symbol will appear on the display when the A/C is on.
Pressing this button when the outside temperature is
below 35ÉF (2ÉC) will make the snow¯ake symbol ¯ash
three times and then it will turn off to let you know the air
conditioning mode is not available. If the air conditioning
is on and the outside temperature drops below 35ÉF
(2ÉC), the snow¯ake symbol will turn off to let you know
the air conditioning mode has been canceled.
3-28

Fan Knob
The fan knob on the left side of the control panel
adjusts the fan speed. To increase air¯ow, turn the knob
clockwise. To decrease air¯ow, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.
9(Off):An off setting, located on the front climate
control panel also allows the driver to turn off the
rear seat passenger seat controls from the front seat.
Temperature Knob
The middle knob on the control panel lets you select the
temperature of the air ¯owing into the passenger
area. Turn the knob clockwise toward the red area for
warmer air. Turn the knob counterclockwise toward
the blue area for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
H(Vent):This setting directs the air through the
headliner outlets.
)(Bi-Level):Air is delivered through the ¯oor outlets
as well as the headliner outlets. The ¯ow can be
divided between vent and ¯oor outlets depending upon
where the knob is placed between the settings.
6(Floor):This setting directs most of the air through
the ¯oor outlets.
To use the rear control, ®rst turn the front control to the
AUX position. Then, the rear control can be used to
adjust the air¯ow speed, temperature, and air¯ow
location.Rear Controls
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Fan Knob
The fan knob on the left side of the control panel
adjusts the fan speed. To increase air¯ow, turn the knob
clockwise. To decrease air¯ow, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.
9(Off):Turn the knob to this position to turn the rear
seat comfort controls on or off.
Temperature Knob
The middle knob on the control panel lets you select the
temperature of the air ¯owing into the passenger
area. Turn the knob clockwise toward the red area for
warmer air. Turn the knob counterclockwise toward
the blue area for cooler air.
Mode Knob
The right knob on the control panel allows you to
choose the direction of air delivery.
H(Vent):This setting directs the air through the
headliner outlets.
)(Bi-Level):Air is delivered through the ¯oor outlets
as well as the headliner outlets. The ¯ow can be
divided between vent and ¯oor outlets depending upon
where the knob is placed between the settings.
6(Floor):This setting directs most of the air through
the ¯oor outlets.
Rear Air Conditioning and Heating
System and Electronic Climate
Controls
If your vehicle is equipped with this system, there are
controls located in the overhead console and on
the back of the console in the rear seat area. The
system can be controlled from the overhead controls or
the rear controls.
Front Controls
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The overhead control has three knobs that control
air¯ow speed, temperature and air¯ow location.
To adjust the air¯ow speed turn the knob located on the
left side of the control panel. To adjust the air
temperature turn the temperature knob on the center of
the control panel to increase or decrease the
temperature. To regulate air¯ow location adjust the right
knob on the control panel.
The system also AUTO settings that can automatically
control the fan speed and/or mode of the air delivery
to the rear seating area.
9(Off):An off setting, located on the overhead
climate control panel also allows the driver to turn off the
rear seat passenger seat controls from the front seat.
The rear seat controls have the following settings:
O(On/Off):Press this button to turn the rear seat
comfort controls on or off.
%(Mode):Press this button to select the air delivery,
and setting, and AUTO mode.
b(Temperature):Press this button up or down to
increase or decrease the temperature setting.
w9x(Fan):Press this button up or down to adjust
the fan speed.Rear Controls
3-35

Trailer Brakes
If your trailer weighs more than 2,000 lbs. (900 kg)
loaded, then it needs its own brakes ± and they must be
adequate. Be sure to read and follow the instructions
for the trailer brakes so you'll be able to install,
adjust and maintain them properly.
If your vehicle is equipped with Stabilitrak
ž, your trailer
cannot tap into the vehicle's hydraulic brake system.
Your trailer brake system can tap into the vehicle's
hydraulic brake system only if:
·The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
·The trailer's brake system will use less than
0.02 cubic inches (0.3 cc) of ¯uid from your vehicle's
master cylinder. Otherwise, both braking systems
won't work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port on the master cylinder that sends the ¯uid
to the rear brakes. But don't use copper tubing for this.
If you do, it will bend and ®nally break off. Use steel
brake tubing.
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't see or smell CO. It can cause
unconsciousness or death. See ªEngine
Exhaustº in the Index. 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.
See ªClimate Controlsº in the Index.
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Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer for
service.
Fuel E-85 (85% Ethanol)
The 8th digit of your vehicle identi®cation number (VIN)
shows the code letter or number that identi®es your
engine. You will ®nd the VIN at the top left of the
instrument panel. See
Vehicle Identi®cation Number
(VIN) on page 5-107.
If your vehicle has the 5.3L V8 engine (VIN Code Z
only), you may use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E-85);
also see
Fuel on page 5-4. In all other engines, including
the 5.3L V8 (VIN Code T), use only regular unleaded
gasoline.Only vehicles that have the 5.3L V8 engine (VIN Code Z)
may use 85% ethanol fuel (E-85).
Many service stations will not have an 85% ethanol fuel
(E-85) pump available. The U. S. Department of
Energy has an alternative fuels website
(http://afdcmap.nrel.gov/nrel/) that can help you ®nd
E-85 fuel. Those stations that do have E-85 should have
a label indicating ethanol content. Do not use the fuel
if the ethanol content is
greaterthan 85%. Your vehicle
may not operate properly if the ethanol content is
greater than 85%.
At a minimum, E-85 should meet ASTM Speci®cation
D 5798.
To insure quick starts in the wintertime, the E-85 fuel
must be formulated properly for your climate according
to ASTM speci®cation D 5798. If you have trouble
starting on E-85, it may be because your E-85 fuel is
not properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to your fuel
tank may improve starting. Your vehicle is designed to
accommodate a mixture of gasoline and E-85 fuel.
For good starting and heater efficiency below 32ÉF
(0ÉC), the fuel mix in the fuel tank should contain no
more than 70% ethanol.
5-7

snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.
While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a speci®ed government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart signi®cantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction ± AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire's ability
to stop on wet pavement as measured under controlled
conditions on speci®ed government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction gradeassigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
Temperature ± A, B, C
The temperature grades are A (the highest), B, and C,
representing the tire's resistance to the generation
of heat and its ability to dissipate heat when tested
under controlled conditions on a speci®ed indoor
laboratory test wheel. Sustained high temperature can
cause the material of the tire to degenerate and
reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a
level of performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly in¯ated and not
overloaded. Excessive speed, underin¯ation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
5-73