light GMC YUKON DENALI 2010 Repair Manual

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.
Manual Operation
D C(Fan Control):Press these buttons to increase or
decrease the fan speed.
Pressing either fan button while in automatic control
places the fan under manual control. The fan setting
remains displayed and the AUTO light turns off. The air
delivery mode remains under automatic control.
H G(Air Delivery Mode Control): Press these buttons
to change the direction of the airflow in the vehicle.
Repeatedly press either button until the desired mode
appears on the display. Pressing either mode button
while the system is off changes the air delivery mode
without turning the system on. Pressing either mode
button while in automatic control places the mode under
manual control.
The air delivery mode setting is displayed and the
AUTO light turns off. The fan remains under automatic
control.
H(Vent): Air is directed to the instrument panel
outlets.
)(Bi-Level): Air is divided between the instrument
panel and floor outlets. Some air is directed towards the
windshield and side window outlets.
6(Floor): Air is directed to the floor outlets, with some
to the windshield, side window outlets, and second row
floor outlets. In this mode, the system automatically
selects outside air.
-(Defog): This mode clears the windows of fog or
moisture. Air is directed to the windshield, floor outlets,
and side window vents. In this mode, the system turns
off recirculation and runs the air conditioning
compressor unless the outside temperature is close to
freezing. The recirculation mode cannot be selected
while in the defog mode.
0(Defrost): This mode removes fog or frost from the
windshield more quickly. Air is directed to the
windshield and side window vents, with some directed
to the floor vents. In this mode, the system
automatically forces outside air into the vehicle and
runs the air conditioning compressor unless the outside
temperature is close to freezing. The recirculation mode
cannot be selected while in the defrost mode.
The passenger temperature control cannot be activated
while in defrost mode. If the PASS button is pressed,
the button indicator flashes three times and will not
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work. If the passenger temperature buttons are
adjusted, the driver temperature indicator changes.
The passenger temperature will not be displayed.
If vent, bi-level, or floor mode is selected again,
the climate control system displays the previous
temperature settings.
Do not drive the vehicle until all the windows are clear.
#(Air Conditioning):Press to turn the air
conditioning (A/C) compressor on and off. An indicator
light comes on to show that the air conditioning is on.
If this button is pressed when the air conditioning
compressor is unavailable, the indicator flashes three
times and then turns off. If the air conditioning is on and
the outside temperature drops below a temperature
which is too cool for air conditioning to be effective,
the air conditioning light turns off to show that the air
conditioning mode has been canceled.
On hot days, open the windows long enough to let hot
inside air escape. This helps to reduce the time it takes
for the vehicle to cool down. It also helps the system to
operate more efficiently.
The air conditioning system removes moisture from the
air, so a small amount of water might drip under the
vehicle while idling or after turning off the engine.
This is normal.
@(Recirculation): Press to turn the recirculation
mode on or off. An indicator light comes on to show that
the recirculation is on.
This mode recirculates and helps to quickly cool the air
inside the vehicle. It can be used to help prevent
outside air and odors from entering the vehicle.
The recirculation mode cannot be used with floor, defog,
or defrost modes. If recirculation is selected with one of
those modes, the indicator light flashes three times and
then turns off. The air conditioning compressor also
comes 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 the fan speed.
The recirculation mode can also be turned off by turning
off the ignition.
REAR : For vehicles with the rear heat and air
conditioning controls. Press to turn the rear climate
control system on or off. See Rear Air Conditioning and
Heating System and Electronic Climate Controls
on
page 4‑24.
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Automatic Operation, If Equipped.
AUTO :Press the air delivery mode button until this
setting is selected to control the inside temperature,
air delivery, and fan speed. AUTO appears in the
display when automatic operation is active.
+/− (Increase/Decrease Temperature) : Press the
+ or −buttons to increase or decrease the cabin
temperature. The rear control temperature display will
show the temperature setting increasing or decreasing.
The display only indicates climate control functions
when the system is in rear independent mode.
Manual Operation
D C(Fan Control): Press these buttons on the rear
seat audio control panel to increase or decrease the
airflow. Pressing the fan up button when the system is
off will turn the system on. The air delivery mode will
remain under automatic control.
+/− (Temperature Control) : Press these buttons to
adjust the temperature of the air flowing into the
passenger area. Press the + button for warmer air and
press the −button for cooler air.
N(Air Delivery Mode Control): Press the mode
button to change the direction of the airflow in the
vehicle. Repeatedly press the button until the desired
mode appears on the display. Multiple presses will cycle
through the delivery selections.
Warning Lights, Gages, and
Indicators
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 the
warning lights and gages could prevent injury.
Warning lights come on when there might be or there
is a problem with one of the vehicle's functions.
Some warning lights come on briefly when the engine
is started to indicate they are working.
Gages can indicate when there might be or there is a
problem with one of the vehicle's functions. Often gages
and warning lights work together to indicate a problem
with the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
could be a problem, check the section that explains
what to do. Follow this manual's advice. Waiting to do
repairs can be costly and even dangerous.
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Speedometer and Odometer
The speedometer shows the vehicle's speed in both
miles per hour (mph) and kilometers per hour (km/h).
The odometer mileage can be checked without the
vehicle running. Simply press the trip stem on the
instrument panel cluster.
If the vehicle ever needs a new odometer installed,
the new one is set to the correct mileage total of the
old odometer.
Trip Odometer
The trip odometer can show how far the vehicle has
been driven since the trip odometer was last set 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 resets it.
To display the odometer reading with the ignition off,
press the reset button.
Tachometer
The tachometer displays the engine speed in
revolutions per minute (rpm).
Safety Belt Reminders
Driver Safety Belt Reminder Light
When the engine is started, a chime sounds for several
seconds to remind a driver to fasten the safety belt,
unless the driver safety belt is already buckled.
The safety belt light
flashes for several
seconds, then comes on
solid for several more.
This chime and light sequence are repeated if the driver
remains unbuckled and the vehicle is in motion. If the
driver safety belt is already buckled, neither the chime
nor the light comes on.
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Passenger Safety Belt Reminder Light
For vehicles equipped with the passenger safety belt
reminder light, several seconds after the engine is
started, a chime sounds for several seconds to remind
the front passenger to buckle their safety belt. The
passenger safety belt light, located on the overhead
console, comes on and stays on for several seconds,
flashes for several more seconds and then comes on
solid for several more.
This chime and light
sequence is repeated if
the passenger remains
unbuckled and the vehicle
is in motion.
If the passenger safety belt is buckled, neither the
chime nor the light comes on.
The front passenger safety belt warning light and chime
may turn on if an object is put on the seat such as a
briefcase, handbag, grocery bag, laptop or other
electronic device. To turn off the warning light and or
chime, remove the object from the seat or buckle the
safety belt.
Airbag Readiness Light
The system checks the airbag's electrical system for
possible malfunctions. If the light stays on it indicates
there is an electrical problem. The system check
includes the airbag sensor, the pretensioners, the
airbag modules, the wiring and the crash sensing and
diagnostic module. For more information on the airbag
system, see Airbag System on page 2‑75.
The airbag readiness light
comes on solid for a
few seconds when the
engine is started. If the
light does not come on
then, have it fixed
immediately.
{WARNING:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
(Continued)
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WARNING: (Continued)
properly. The airbags in the vehicle might not
inflate in a crash, or they could even inflate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbag
Driver Information Center (DIC) message can also
come on. See DIC Warnings and Messages
on
page 4‑56for more information.
Passenger Airbag Status Indicator
If the vehicle has the airbag status indicator pictured in
the following illustration, then the vehicle has a
passenger sensing system for the right front passenger
position. The passenger airbag status indicator is on the
overhead console. See Passenger Sensing System
on
page 2‑85for important safety information. In addition, if the vehicle has a passenger sensing
system for the right front passenger position, the label
on the vehicle's sun visors refers to
“ADVANCED
AIRBAGS”.
United StatesCanada
When the vehicle is started, the passenger airbag
status indicator will light ON and OFF, or the symbols
for on and off, for several seconds as a system check.
If you are using remote start, if equipped, to start the
vehicle from a distance, you may not see the system
check.
Then, after several more seconds, 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
frontal airbag.
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If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger frontal airbag is enabled (may inflate).
If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger frontal
airbag.
If, after several seconds, both status indicator lights
remain on, or if there are no lights at all, there may be
a problem with the lights or the passenger sensing
system. See your dealer/retailer for service.
{WARNING:
If the airbag readiness light ever comes on and
stays on, it means that something may be wrong
with the airbag system. To help avoid injury to
yourself or others, have the vehicle serviced right
away. SeeAirbag Readiness Light
on page 4‑28
for more information, including important safety
information.
Charging System Light
This light comes on briefly
when the ignition key is
turned to START, but the
engine is not running,
as a check to show it is
working.
If it does not, have the vehicle serviced by your
dealer/retailer.
The light should go out once the engine starts. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system message
in the Driver Information Center (DIC) can also appear.
See DIC Warnings and Messages
on page 4‑56for
more information. This light could indicate that there
are problems with a generator drive belt, or that there
is an electrical problem. Have it checked right away.
If the vehicle must be driven a short distance with the
light on, turn off accessories, such as the radio and
air conditioner.
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Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle
is driven with the parking brake engaged, a chime
sounds when the vehicle speed is greater than
8 km/h (5 mph).
The vehicle's hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop the vehicle. For good braking, both
parts need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake fluid.
SeeBrakes
on page 6‑38for more information.
United StatesCanada This light comes on briefly when the ignition key is
turned to ON/RUN. If it does not come on then, have it
fixed so it is ready to warn if there is a problem.
{WARNING:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the floor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
See Towing Your Vehicle on page 5‑37.
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Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briefly when the engine
is started.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the ABS light stays on, turn the ignition off. If the light
comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on,
or comes on again while driving, the vehicle needs
service. If the regular brake system warning light is not
on, the vehicle still has brakes, but not antilock brakes.
If the regular brake system warning light is also on, the
vehicle does not have antilock brakes and there is a
problem with the regular brakes. See Brake System
Warning Light on page 4‑32.
For vehicles with a Driver Information Center (DIC),
see DIC Warnings and Messages
on page 4‑56for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briefly
while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light flashes if the system is active and is working
to assist the driver with directional control of the vehicle
in difficult driving conditions.
See StabiliTrak
®Systemon page 5‑6for more
information.
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Engine Coolant Temperature Gage
United StatesCanada
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
fluctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
See Engine Overheating on page 6‑32.
Tire Pressure Light
For vehicles with a tire
pressure monitoring
system, this light comes
on briefly when the engine
is started. It provides
information about tire
pressures and the Tire
Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires is
significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. See Driver
Information Center (DIC)
on page 4‑42for more
information. Stop and check the tires as soon as it is
safe to do so. If underinflated, inflate to the proper
pressure. See Inflation - Tire Pressure
on page 6‑64for more information.
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