2004 GMC YUKON air condition

Seat Position Sensors
Vehicles with dual stage air bags are also equipped with
special sensors which enable the sensing system to
monitor the position of both the driver and passenger
front seats. The seat position sensor provides
information which is used to determine if the air bags
should deploy at a reduced level or at full deployment.
Side Impact Air Bags
Your vehicle may or may not have a side impact air
bag. SeeAir Bag Systems on page 1-72. 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.
Air Bag Systems
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. See Off-Road
Driving with Your Four-Wheel Drive Vehicle in the
Index for tips on off-road driving.
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Passenger Sensing System
If your rearview mirror has one of the indicators pictured
in the following illustrations, your vehicle has a passenger
sensing system. The indicator will be visible when you
turn your ignition key to START or RUN. The words ON
and OFF or the symbol for on and off, will be visible on
the rearview mirror during the system check. When the
system check is complete, either the word ON or the word
OFF, or the symbol for on or the symbol for off will be
visible. SeePassenger Air Bag Status Indicator on
page 3-43. If your rearview mirror does not have either of
the indicators pictured, then your vehicle does not have
the passenger sensing system.The passenger sensing system will turn off the right
front passenger’s frontal air bag under certain
conditions. The driver’s air bag and the side air bags
are not part of the passenger sensing system.
The passenger sensing system works with sensors that
are part of the right front passenger’s seat and safety
belt. The sensors are designed to detect the presence of
a properly-seated occupant and determine if the
passenger’s frontal air bag should be enabled (may
inate) or not.
Accident statistics show that children are safer if they
are restrained in the rear rather than the front seat.
General Motors recommends that child restraints
be secured in a rear seat, including an infant riding in a
rear-facing infant seat, a child riding in a forward-facing
child seat and an older child riding in a booster seat.
Your vehicle has a rear seat that will accommodate
a rear-facing child restraint. A label on your sun visor
says, “Never put a rear-facing child seat in the
front.” This is because the risk to the rear-facing child is
so great, if the air bag deploys. Passenger Air Bag Status Indicator – United States
Passenger Air
Bag Status
Indicator – Canada
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OnStar®System
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
Remote Door Unlock
Remote Diagnostics
Online Concierge
Directions and Connections Plan

All Safe and Sound Plan services
Route Support
RideAssist
Information and Convenience Services
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Instrument Panel Overview...............................3-4
Hazard Warning Flashers................................3-6
Other Warning Devices...................................3-7
Horn.............................................................3-7
Tilt Wheel.....................................................3-7
Turn Signal/Multifunction Lever.........................3-8
Exterior Lamps.............................................3-15
Interior Lamps..............................................3-19
Accessory Power Outlets...............................3-21
Ashtrays and Cigarette Lighter........................3-21
Climate Controls............................................3-22
Climate Control System.................................3-22
Dual Climate Control System..........................3-23
Dual Automatic Climate Control System...........3-27
Rear Air Conditioning System.........................3-34
Rear Air Conditioning and Heating System.......3-35
Rear Air Conditioning and Heating System
and Electronic Climate Controls...................3-38
Warning Lights, Gages and Indicators.............3-40
Warning Lights, Gages, and Indicators.............3-40
Instrument Panel Cluster................................3-41
Speedometer and Odometer...........................3-42
Tachometer.................................................3-42
Safety Belt Reminder Light.............................3-42
Air Bag Readiness Light................................3-43
Passenger Air Bag Status Indicator.................3-43Battery Warning Light....................................3-45
Voltmeter Gage............................................3-45
Brake System Warning Light..........................3-46
Anti-Lock Brake System Warning Light.............3-47
Traction Off Light..........................................3-48
Engine Coolant Temperature Gage..................3-49
Transmission Temperature Gage.....................3-49
Tire Pressure Light.......................................3-51
Malfunction Indicator Lamp.............................3-51
Oil Pressure Gage........................................3-55
Cruise Control Light......................................3-56
Four-Wheel-Drive Light..................................3-56
Tow/Haul Mode Light....................................3-56
Fuel Gage...................................................3-57
Low Fuel Warning Light.................................3-57
Driver Information Center (DIC).......................3-58
DIC Operation and Displays...........................3-58
DIC Warnings and Messages.........................3-70
Audio System(s).............................................3-77
Setting the Time for Radios without Radio
Data Systems (RDS)..................................3-77
Setting the Time for Radios with Radio
Data Systems (RDS)..................................3-78
AM-FM Radio...............................................3-78
Radio with CD..............................................3-81
Radio with Cassette and CD..........................3-92
Section 3 Instrument Panel
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To change the current mode, select one of the following:
H(Vent):This mode directs air to the instrument
panel vents.
)(Bi-Level):This mode directs half of the air to the
instrument panel vents; then directs most of the
remaining air to the oor vents. A little air is directed
toward the windshield and the side window vents. Cooler
air is directed to the upper vents and warmer air to the
oor vents.
6(Floor):This mode directs most of the air to the
oor vents with a little air directed to the windshield and
the side window vents.
h(Recirculation):The 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. Press this button to turn the recirculation mode
on or off. The light on the recirculation button will
illuminate. Recirculation cannot be used in oor, blend or
defrost modes. An indicator on the button will light up,
ash three times and turn off when recirculation is
selected in these modes.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 blend or defrost mode and increase fan speed.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. This lever also adjusts
the temperature to the center console outlets (if
equipped).
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.
#(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.
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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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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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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.
Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature, the
air delivery, 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 display will change to
show the current driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
within ve seconds to display the passenger’s set
temperature.If the driver and passenger’s temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additional ve
seconds. To make the passenger’s temperature the
same as the driver’s press and hold the AUTO
button for about four seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will run
when the outside temperature is over about
40°F (4°C). The air inlet will normally be set to
outside air. If it’s hot outside, the air inlet may
automatically switch to recirculate inside air to help
quickly cool down your vehicle. The light on the
button will illuminate in recirculation.
2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°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 will not cause
the vehicle to heat or cool any faster.
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