light GMC YUKON 2006 Workshop Manual

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:Do not use anything sharp on the inside of
the rear window. If you do, you could cut or
damage the warming grid, and the repairs would not
be covered by your warranty. Do not attach a
temporary vehicle license, tape, a decal or anything
similar to the defogger grid.
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.
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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.
Be careful not to cover the sensor located on the top of
the instrument panel near the windshield. This sensor
regulates air temperature based on sun load, and
also turns on your headlamps.
To avoid blowing cold air in cold weather, the system
will delay turning on the fan until warm air is available.
The length of delay depends on the engine coolant
temperature. Pressing the fan switch will override this
delay and change the fan to a selected speed.
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.
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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 airow in your vehicle; repeatedly press
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 “Defogging and Defrosting” 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.
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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.
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 10 seconds, the display will
change to show the driver’s 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 10 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
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.
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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: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.
Outlet Adjustment
Use the air outlets located in the center and on the side
of your instrument panel 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.
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.
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Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages on
your vehicle. The pictures will help you locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you
will see in the details on the next few pages, some
warning lights come on briey when you start the engine
just to let you know they are working. If you are familiar
with this section, you should not be alarmed when this
happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there is a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages shows
there may be a problem, check the section that tells you
what to do about it. Please follow this manual’s advice.
Waiting to do repairs can be costly – and even
dangerous. So please get to know your warning lights
and gages. They are a big help.
Your vehicle also has a Driver Information Center (DIC)
that works along with warning lights and gages.
SeeDIC Warnings and Messages on page 3-56.
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Instrument Panel Cluster
Your instrument cluster is designed to let you know at a glance how your vehicle is running. You’ll know how fast you’re
going, about how much fuel you have and many other things you’ll need to know to drive safely and economically.United States Heavy Duty Transmission version shown. Canada and Light Duty
Transmission Clusters similar.
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Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
engine hours, turn the ignition off, press and hold the
reset button for at least four seconds. The hour meter
will be displayed for up to 30 seconds, or until the
ignition is turned on. SeeDIC Operation and Displays
on page 3-53for more information.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer
to zero.
Press the reset button, located on the instrument panel
cluster next to the trip odometer display, to toggle
between the trip odometer and the regular odometer.
Holding the reset button for approximately one second
while the trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
be provided for several seconds to remind people to
buckle their safety belts. The driver safety belt light will
also be provided and stay on for several seconds,
then it will ash for several more. You should buckle
your seat belt.
This chime and light will be
repeated if the driver
remains unbuckled and the
vehicle is in motion.
SeeDIC Warnings and Messages on page 3-56for
more information on driver and passenger safety
belt reminders.
If the driver’s belt is buckled, neither the chime nor the
light will come on.
SeePassenger Sensing System on page 1-82for more
information.
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Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensors, the airbag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
airbag system, seeAirbag System on page 1-74.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. This means
the system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your airbag
system may not work properly. Have your vehicle
serviced right away.
Passenger Airbag Status Indicator
If your vehicle has a passenger sensing system,
your rearview mirror will have a passenger airbag status
indicator.
When the ignition key is turned to RUN or START,
the passenger airbag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,
Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
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the status indicator will light either ON or OFF, or either
the on or off symbol to let you know the status of the
right front passenger’s frontal airbag.
If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger’s frontal airbag is enabled (may inate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger’s seat, it means that the
passenger sensing system has not turned off
the passenger’s frontal airbag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger’s
airbag inates. This is because the back of the
rear-facing child restraint would be very close
to the inating airbag. Do not use a rear-facing
child restraint in the right front passenger’s
seat if the airbag is turned on.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 airbag deploys.
{CAUTION:
Even though the passenger sensing system is
designed to turn off the passenger’s frontal
airbag if the system detects a rear-facing child
restraint, no system is failsafe, and no one can
guarantee that an airbag will not deploy under
some unusual circumstance, even though it is
turned off. We recommend that rear-facing
child restraints be secured in the rear seat,
even if the airbag is off.
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