2007 GMC YUKON XL light

Air Conditioning
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(Air Conditioning):Press this button to turn
the air conditioning (A/C) compressor on and
off. When air conditioning is selected, an indicator
light will come on to let you know that the air
conditioning has been activated.
Pressing this button when the outside temperature
is too cool for air conditioning will make the air
conditioning indicator ash three times and
then 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 a
temperature which is too cool for air conditioning
to be effective, the air conditioning light will turn off
to let you know 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 your vehicle to cool down. It also
helps the system to operate more efficiently.
The air conditioning system removes moisture from
the air, so you may sometimes notice a small
amount of water dripping underneath your vehicle
while idling or after turning off the engine. This
is normal.
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 clear fog or frost from your
windshield.
Use the mode up and down arrows to select the
defog or defrost modes.
-(Defog):The defog mode is used to clear the
windows of fog or moisture and warm the
passengers. This mode directs air to the
windshield, oor outlets, and side window vents.
When you select 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. Do not drive
the vehicle until all the windows are clear.
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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 254.
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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).
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.
If the driver’s belt is buckled, neither the chime nor
the light will come on.
SeePassenger Sensing System on page 100for
more information.
226

Passenger Safety Belt Reminder
Light
Several seconds after the key is turned to RUN or
START, a chime will sound for several seconds
to remind the front passenger to buckle their safety
belt. The passenger safety belt light will also
come on and stay on for several seconds, then it
will ash for several more.
This chime and light will
be repeated if the
passenger remains
unbuckled and
the vehicle is in motion.
If the passenger’s safety belt is buckled, neither
the chime nor the light will come on.
Airbag Readiness Light
There is an airbag readiness light on the
instrument panel, 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 wiring and the crash sensing and diagnostic
module. For more information on the airbag
system, seeAirbag System on page 90.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
Then the light should go
out. This means the
system is ready.
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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.
{CAUTION:
If the airbag readiness light stays on after
you start your vehicle, it means the airbag
system may not be working properly. The
airbags in your vehicle may not inate in
a crash, or they could even inate without
a crash. To help avoid injury to yourself
or others, have your vehicle serviced right
away if the airbag readiness light stays on
after you start your vehicle.
The airbag readiness light should ash for a few
seconds when you turn the ignition key to RUN.
If the light doesn’t come on then, have it xed so it
will be ready to warn you if there is a problem.
Passenger Airbag Status Indicator
Your vehicle has the passenger sensing system.
Your overhead console has 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, 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.
Passenger
Airbag Status
Indicator – United
StatesPassenger
Airbag Status
Indicator – Canada
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If, after several seconds, all 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 for service.
{CAUTION:
If the off indicator and the airbag
readiness light ever come on together, it
means that something may be wrong with
the airbag system. If this ever happens,
have the vehicle serviced promptly,
because an adult-size person sitting in the
right front passenger seat may not have
the protection of the frontal airbag. See
Airbag Readiness Light on page 227.
Charging System Light
The charging system
light will come on briey
when you turn on the
ignition, but the
engine is not running,
as a check to show you
it is working.
It should go out once the engine is running.
If it stays on, or comes on while you are driving,
you may have a problem with the charging system.
It could indicate that you have problems with the
generator, the generator drive belt, or another
electrical problem. Have it checked right away.
Driving while this light is on could drain your
battery.
When this light comes on, the DIC will also display
the SERVICE BATTERY NOT CHARGING
SYSTEM message. SeeDIC Warnings and
Messages on page 254for more information.
If you must drive a short distance with the light on,
be certain to turn off all your accessories, such as
the radio and air conditioner, to reduce the drain on
your battery.
230

Voltmeter Gage
When your engine is not
running, but the ignition
is in RUN, this gage
shows your battery’s
state of charge in
DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging
system regulates voltage based on the state of the
battery for improved fuel economy and battery
life. The gage may transition from a higher to lower
or a lower to higher reading, this is normal.
Readings between the low and high warning zones
indicate the normal operating range.Readings in the low warning zone may occur
when a large number of electrical accessories are
operating in the vehicle and the engine is left at
an idle for an extended period. This condition
is normal since the charging system is not able to
provide full power at engine idle. As engine
speeds are increased, this condition should correct
itself as higher engine speeds allow the charging
system to create full power. If there is a problem
with the battery charging system, this light
will come on or the SERVICE BATTERY
CHARGING SYSTEM DIC message will display.
SeeDIC Warnings and Messages on page 254
andCharging System Light on page 230for more
information.
231

Brake System Warning Light
With the ignition on, the brake system warning
light will come on when you set the parking brake.
If you try to drive with the parking brake engaged,
a chime will sound when the vehicle speed is
greater than 3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided
into two parts. If one part is not working, the other
part can still work and stop you. For good
braking, though, you need both parts working well.
If the warning light comes on and a chime sounds
there could be a brake problem. Have your brake
system inspected right away.
This light may also come on due to low brake uid.
SeeBrakes on page 463for more information.This light should come on briey when you turn
the ignition key to RUN. If it does not come
on then, have it xed so it will be ready to warn
you if there’s a problem.
If the light comes on while you are driving, pull off
the road and stop carefully. You may notice
that the pedal is harder to push or may go closer
to the oor. It may take longer to stop. If the
light is still on, have the vehicle towed for service.
SeeTowing Your Vehicle on page 400.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light
is on. Driving with the brake system
warning light on can lead to an accident.
If the light is still on after you have pulled
off the road and stopped carefully, have
the vehicle towed for service.
United StatesCanada
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