light GMC YUKON XL 2010 Manual Online

{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
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 4‑61for 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 2‑94for 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 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 4‑32
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.
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 4‑61for
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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Voltmeter Gauge
When the engine is not
running, but the ignition is
on, this gauge shows the
battery's state of charge
in DC volts.
When the engine is running, the gauge 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 gauge 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. The gauge may also read low during the fuel
economy mode, this is normal. 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. See
DIC Warnings
and Messages
on page 4‑61and Charging System
Lighton page 4‑34for more information.
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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 6‑42for 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.
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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.
SeeTowing Your Vehicle on page 5‑41.
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.
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 4‑36.
For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages
on page 4‑61for all
brake related DIC messages.
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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.
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.
Engine Coolant Temperature Gauge
United StatesCanada
This gauge shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gauge
reads 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
gauge reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
See Engine Overheating on page 6‑36.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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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. SeeDriver
Information Center (DIC)
on page 4‑47for 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 6‑72for more information.
When the Light Flashes First and Then is
On Steady
This indicates that there may be a problem with the Tire
Pressure Monitor System. The light flashes for about a
minute and stays on steady for the remainder of the
ignition cycle. This sequence repeats with every ignition
cycle. SeeTire Pressure Monitor Operation
on
page 6‑75for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on,
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.
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If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.
Notice:If the vehicle is continually driven with this
light on, after a while, the emission controls might
not work as well, the vehicle's fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that
might not be covered by the vehicle warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake, or fuel system
of the vehicle or the replacement of the original
tires with other than those of the same Tire
Performance Criteria (TPC) can affect the vehicle's
emission controls and can cause this light to come
on. Modifications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 6‑4. This light comes on during a malfunction in one of
two ways:
Light Flashing:
A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the vehicle off, wait at least 10 seconds, and
restart the engine. If the light is still flashing, follow the
previous steps and see your dealer for service as soon
as possible.
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Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
.Make sure the fuel cap is fully installed. See Filling
the Tankon page 6‑11. The diagnostic system
can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap
allows fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should
turn the light off.
.If the vehicle has been driven through a deep
puddle of water, the vehicle's electrical system
might be wet. The condition is usually corrected
when the electrical system dries out. A few driving
trips should turn the light off.
.Make sure to fuel the vehicle with quality fuel.
Poor fuel quality causes the engine not to run as
efficiently as designed and can cause: stalling
after start-up, stalling when the vehicle is changed
into gear, misfiring, hesitation on acceleration,
or stumbling on acceleration. These conditions
might go away once the engine is warmed up.
If one or more of these conditions occurs, change
the fuel brand used. It will require at least one full
tank of the proper fuel to turn the light off.
See Gasoline Octane on page 6‑7.
If none of the above have made the light turn off,
your dealer can check the vehicle. The dealer has the
proper test equipment and diagnostic tools to fix any
mechanical or electrical problems that might have
developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments may have
programs to inspect the on-vehicle emission control
equipment For the inspection, the emission system
test equipment is connected to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument panel to the left of the
steering wheel. See your dealer if assistance is needed.The vehicle may not pass inspection if:
.the check engine light is on with the engine
running, or if the light does not come on when
the ignition is turned to ON/RUN while the engine
is off.
.the critical emission control systems have not been
completely diagnosed by the system. This can
happen if the battery has recently been replaced or
if the battery has run down. The diagnostic system
evaluates critical emission control systems during
normal driving. This can take several days of
routine driving. If this has been done and the
vehicle still does not pass the inspection, your
dealer can prepare the vehicle for inspection.
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