2004 CHEVROLET TAHOE air conditioning

Defogging and Defrosting
You can use either defog or front defrost to clear fog or
frost from your windshield. Use the defog mode to
clear the windows of fog or moisture. Use the front
defrost button to defrost the front windshield.
-(Defog):Use this setting to clear the windows of fog
or moisture. Press the mode button to select this
setting. This setting will deliver air to the oor and
windshield outlets.
0(Front Defrost):Press the front defrost button to
defrost the windshield. 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.
Rear Window Defogger
If your vehicle has this feature, 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 turn off about 10 minutes
after the button is pressed. If you need additional
warming time, press the button again.
If your vehicle is equipped with heated mirrors this
button will activate them.
Notice:Using a razor blade or sharp object to clear
the inside rear window may damage the rear
window defogger. Repairs would not be covered by
your warranty. Do not clear the inside of the rear
window with sharp objects.
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Outlet Adjustment
Use the air outlets located
in the center and on the
side of your instrument
panel to direct the airow.
Your vehicle has air outlets that allow you to adjust the
direction and amount of airow inside the vehicle.
Move the louvers up or down. Use the thumbwheel next
to or underneath the outlet to close the louvers. For
the most efficient airow and temperature control, keep
the outlet in the fully opened position.
Rear seat outlets can be used to adjust airow toward
either seating area, the oor or upward. Move the center
louvers up or down to direct the airow.
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.
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, etc., may affect
the performance of the heating and air conditioning
system. Check with your dealer before adding
equipment to the outside of your vehicle.
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Rear Air Conditioning System
If your vehicle is equipped with the optional rear air
conditioner it has two rear air conditioning fan speed
selectors. One fan speed selector is located in the
overhead console and the other is located in the
headliner above the second row seats.
To increase and decrease the ow of cooled air to the
rear vents, turn the knob to the fan speed you want.
The knob has three speed positions. To increase
the ow of cooled air, turn the knob clockwise. To
decrease the ow of cooled air, turn it counterclockwise.
To turn the fan off, turn the knob to the off position.To operate the rear system using the front control, just
turn the knob to the fan position you want.
To use the rear control, rst turn the front control to the
AUX position. Then, the rear control can be used to
increase and decrease the airow.
Front Control
Rear Control
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Rear Air Conditioning and Heating
System
If your vehicle is equipped with this system, there are
two rear heat and air conditioning controls. One control
is located in the overhead console and the other is
located in the headliner above the second row seats.
The system can be controlled from the front controls as
well as the rear controls.
The front control has three knobs that control airow
speed, temperature and airow location.
Fan Knob
The fan knob on the left side of the control panel
adjusts the fan speed. To increase airow, turn the knob
clockwise. To decrease airow, 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. Front Control
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Rear Air Conditioning and Heating
System and Electronic Climate
Controls
With this system the front or rear passengers can
control the air temperature, air ow and fan speed for
the rear seat passengers. The climate control has
an overhead control near the driver and a control on the
back of the center console.
Driver Overhead Control
To control the rear climate control from the front seat
position, use the driver overhead control. The rear
console control must be on.AUX:Turn the knob, located on the left side of the
control panel, to this position to allow the rear seat
passengers to have control over the rear climate control
system. See “Rear Passenger Console Control” later
for more information.
9(Off):Turn the knob, located on the left side of the
control panel, to this position to turn the rear climate
control system off.
9(Fan):To adjust the airow speed, turn the fan
knob located on the left side of the control panel to the
desired setting. Choose AUTO if you want the system
to automatically choose the fan speed to maintain
a selected temperature. See “Auto Mode” later in this
section for more information on using this feature.
°F (°C):To adjust the air temperature, turn the
temperature knob on the center of the control panel. For
cooler or warmer air turn the knob counterclockwise
toward 66°F (19°C) or clockwise toward 82°F (27°C).
To regulate the airow direction, adjust the right knob on
the control panel. Turn the knob clockwise for oor
vent airow or counterclockwise for headliner vent
airow. Generally, the upper vents are used for air
conditioning and the oor vents for heating. The knob
can be set to any blend setting. Choose AUTO if
you want the system to automatically regulate the
airow. See “Auto Mode” later in this section for more
information on using this feature. Front Controls
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(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter “LT” as
the rst two characters in the tire size means a light
truck tire engineered to standards set by the U. S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is “75,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall is
75% as high as it is wide.(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from “A” to “Z”. The light truck tire size example
above shows dual or single tire congurations.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. Light Truck (LT-Metric) Tire
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Fuses Usage
SEO B2 Off-Road Lamps
4WSVent Solenoid
Canister/Quadrasteer Module
Power
RR HVAC Rear Climate Control
AUX PWRAuxiliary Power
Outlet — Console
IGN 1 Ignition Relay
PCM 1 Powertrain Control Module
ETC/ECMElectronic Throttle Control,
Electronic Brake Controller
IGN EInstrument Panel Cluster,
Air Conditioning Relay,
Turn Signal/Hazard Switch,
Starter Relay
RTD Ride Control
TRL B/U Backup Lamps Trailer Wiring
PCM BPowertrain Control Module,
Fuel Pump
F/PMP Fuel Pump (Relay)Fuses Usage
B/U LPBack-up Lamps, Automatic
Transmission Shift Lock
Control System
RR DEFOG Rear Window Defogger
HDLP-HI Headlamp High Beam Relay
PRIME Not Used
SIRSupplemental Inatable
Restraint System
FRT PARKFront Parking Lamps,
Sidemarker Lamps
DRL Daytime Running Lamps (Relay)
SEO IGN Rear Defog Relay
TBC IGN1 Truck Body Controller Ignition
HI HDLP-LT High Beam Headlamp-Left
LH HID Not Used
DRL Daytime Running Lamps
IPC/DICInstrument Panel Cluster/Driver
Information Center
HVAC/ECAS Climate Control Controller
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Fuses Usage
CIG LTR Cigarette Lighter
HI HDLP-RT High Beam Headlamp-Right
HDLP-LOW Headlamp Low Beam Relay
A/C COMP Air Conditioning Compressor
A/C COMPAir Conditioning Compressor
Relay
RR WPR Rear Wiper/Washer
RADIO Audio System
SEO B1Mid Bussed Electrical Center,
HomeLink, Rear Heated Seats
LO HDLP-LT Headlamp Low Beam-Left
BTSIBrake Transmission Shift
Interlock System
CRANK Starting System
LO HDLP-RT Headlamp Low Beam-RightFuses Usage
FOG LP Fog Lamp Relay
FOG LP Fog Lamps
HORN Horn Fuse
HORN Horn Relay
W/S WASHWindshield and Rear Window
Washer Pump Relay
W/S WASHWindshield and Rear Window
Washer Pump
INFO OnStar/Rear Seat Entertainment
RADIO AMP Radio Amplier
RH HID Not Used
EAP Electric Adjustable Pedals
TREC All-Wheel Drive Module
SBA Supplemental Brake Assist
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