warning light GMC YUKON XL 2007 User Guide

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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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.
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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.
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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.
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232

Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will
come on when you start
your engine and may
stay on for several
seconds.
That’s normal. If the light does not come on then,
have it xed so it will be ready to warn you if
there is a problem.If the light stays on, or comes on when you are
driving, your vehicle needs service. You will
also hear a chime sound when the light is on
steady. If the regular brake system warning light is
not on, you still have brakes, but you do not
have anti-lock brakes. If the regular brake system
warning light is also on you do not have anti-lock
brakes and there is a problem with your regular
brakes. In addition to both lights, you will also hear
a chime sound on the rst occurrence of a
problem and each time the vehicle is shut off and
then restarted. SeeBrake System Warning
Light on page 232.
The anti-lock brake system warning light should
come on briey when you turn the ignition
key to RUN. If the light does not come on then,
have it xed so it will be ready to warn you if there
is a problem.
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StabiliTrak®Indicator Light
If equipped, this warning
light should come on
briey when the engine
is started.
If the warning light does not come on then, have it
xed so it will be ready to warn you if there is a
problem. If it stays on, or comes on when you are
driving, there may be a problem with your
StabiliTrak
®system and your vehicle may need
service. When this warning light is on, the system
is off and will not limit wheel spin. Adjust your
driving accordingly.
This light will also ash when the StabiliTrak
®
system is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time
when the system is turned on, your vehicle needs
service. SeeStabiliTrak
®System on page 348
for more information.
Engine Coolant Temperature Gage
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 uctuate 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.
SeeEngine Overheating on page 452.
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234

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have
or may begin programs to inspect the emission
control equipment on your vehicle. Failure to pass
this inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
check engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle
would be considered not ready for inspection. This
can happen if you have recently replaced your
battery or if your battery has run down. The
diagnostic system is designed to evaluate critical
emission control systems during normal driving.
This may take several days of routine driving. If you
have done this and your vehicle still does not pass
the inspection for lack of OBD system readiness,
your GM dealer can prepare the vehicle for
inspection.
Oil Pressure Gage
The oil pressure gage shows the engine oil
pressure in psi (pounds per square inch) when
the engine is running. Canadian vehicles indicate
pressure in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above
the low pressure zone indicate the normal operating
range. When the oil pressure reaches the low
pressure zone, the “OIL PRESSURE LOW STOP
ENGINE” message will appear in the Driver
Information Center. SeeDIC Warnings and
Messages on page 254andEngine Oil on
page 438for more information.
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239

Fuel Gage
The fuel gage, when the ignition is on, tells you
about how much fuel you have left in your tank.
The gage will rst indicate empty before you
are out of fuel, and you should get more fuel as
soon as possible.
When the fuel tank is low, the FUEL LEVEL LOW
message will appear. SeeDIC Warnings and
Messages on page 254.
Here are some situations you may experience with
your fuel gage. None of these indicate a problem
with the fuel gage.
At the gas station, the fuel pump shuts off
before the gage reads full.
It takes a little more or less fuel to ll up than
the fuel gage indicated. For example, the
gage may have indicated the tank was half full,
but it actually took a little more or less than
half the tank’s capacity to ll the tank.
The gage goes back to empty when you turn
off the ignition.
Low Fuel Warning Light
This light, under the fuel
gage, will come on
briey when you
are starting the engine.
This light and a chime will come on when the fuel
tank is low on fuel. There will also be a “FUEL
LEVEL LOW” message on the Driver Information
Center, seeDIC Warnings and Messages on
page 254for more information. When you add fuel
this light and message should go off. If it does
not, have your vehicle serviced.United StatesCanada
243

CHANGE ENGINE OIL SOON
This message will display when the engine oil
needs to be changed. When you change the
engine oil, be sure to reset the CHANGE ENGINE
OIL SOON message. SeeEngine Oil Life
System on page 441for information on how to
reset the message. This message will clear itself
after 10 seconds until the next ignition cycle
or until the message is reset. SeeEngine Oil on
page 438andScheduled Maintenance on
page 555for more information.
CHECK TIRE PRESSURE
If your vehicle has a Tire Pressure Monitor (TPM)
system, this message will display when the
pressure in one or more of the vehicle’s tires need
to be checked. This message will also display
LEFT FRONT, RIGHT FRONT, LEFT REAR, or
RIGHT REAR to indicate which tire needs to
be checked. You can receive more than one tire
pressure message at a time. To read the other
messages that may have been sent at the same
time, press the set/reset button or the trip
odometer reset stem. If a tire pressure message
appears on the DIC, stop as soon as you can.Have the tire pressures checked and set to those
shown on your Tire Loading Information Label.
SeeTires on page 482,Loading Your Vehicle on
page 390, andInation - Tire Pressure on
page 490. The DIC display also shows the tire
pressure values for the front and rear tires
by pressing the vehicle information button.
See“DIC Operation and Displays (With DIC
Buttons)”earlier in this section. If the tire pressure
is low, the low tire pressure warning light will
come on. SeeTire Pressure Light on page 235.
DRIVER DOOR OPEN
If the driver’s door is not fully closed and the
vehicle is in a drive gear, this message will display
and a chime will sound. Stop and turn off the
vehicle, check the door for obstructions, and close
the door again. Check to see if the message
still appears on the DIC.
255

SERVICE BATTERY CHARGING
SYSTEM
On some vehicles, if there is a problem with the
battery charging system, this message will display.
Under certain conditions, the battery warning
light may also turn on in the instrument panel
cluster. SeeCharging System Light on page 230.
Driving with this problem could drain the battery.
Turn off all unnecessary accessories. Have
the electrical system checked as soon as possible.
See your GM dealer.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will display along with the brake system
warning light. SeeBrake System Warning Light
on page 232. If this message appears, stop
as soon as possible and turn off the vehicle.
Restart the vehicle and check for the message on
the DIC display. If the message is still displayed
or appears again when you begin driving, the
brake system needs service as soon as possible.
See your GM dealer.
SERVICE BRAKES SOON
If there is a problem with the brake system, this
message will display. If this message appears,
stop as soon as possible and turn off the vehicle.
Restart the vehicle and check for the message
on the DIC display. If the message is still displayed
or appears again when you begin driving, the
brake system needs service. See your GM dealer.
SERVICE PARK ASSIST
If your vehicle has the Ultrasonic Rear Parking
Assist (URPA) system, this message will display
if there is a problem with the URPA system. Do not
use this system to help you park. SeeUltrasonic
Rear Parking Assist (URPA) on page 205for more
information. See your GM dealer for service.
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