warning light GMC YUKON 2009 Owner's Guide

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage
reads 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 5-35.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started and
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 signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-64for more
information. Stop and check the tires as soon as it is
safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-62for more
information. United StatesCanada
3-43

Low Fuel Warning Light
This light, under the fuel
gage, comes on briey
while the engine is being
started.
This light and a chime comes on when the fuel tank is low
on fuel. The Driver Information Center also displays a
“FUEL LEVEL LOW” message. SeeDIC Warnings and
Messages on page 3-64for more information. When fuel
is added this light and message should go off. If it does
not, have the vehicle serviced by your dealer/retailer.
Driver Information Center (DIC)
Your vehicle has a Driver Information Center (DIC).
The DIC displays information about your vehicle. It also
displays warning messages if a system problem is
detected.
All messages will appear in the DIC display located
below the tachometer in the instrument panel cluster.
The DIC comes on when the ignition is on. After a short
delay, the DIC will display the information that was
last displayed before the engine was turned off.
If your vehicle has DIC buttons, see “DIC Operation and
Displays (With DIC Buttons)” later in this section and
DIC Vehicle Customization (With DIC Buttons) on
page 3-74for the displays available.
If your vehicle does not have DIC buttons, see “DIC
Operation and Displays (Without DIC Buttons)” later in
this section for the displays available.
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DIC Warnings and Messages
Messages are displayed on the DIC to notify the driver
that the status of the vehicle has changed and that
some action may be needed by the driver to correct the
condition. Multiple messages may appear one after
another.
Some messages may not require immediate action, but
you can press any of the DIC buttons on the instrument
panel or the trip odometer reset stem on the instrument
panel cluster to acknowledge that you received the
messages and to clear them from the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
If your vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. When you change the engine oil, be sure to
reset the CHANGE ENGINE OIL SOON message. See
Engine Oil Life System on page 5-18for information on
how to reset the message. SeeEngine Oil on page 5-15
andScheduled Maintenance on page 6-4for more
information.
CHECK TIRE PRESSURE
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the pressure in one
or more of the vehicle’s tires needs to be checked. This
message also displays 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 the Tire Loading Information label. See
Tires on page 5-62,Loading the Vehicle on page 4-33,
andInflation - Tire Pressure on page 5-70. The DIC also
shows the tire pressure values. See “DIC Operation and
Displays (With DIC Buttons)” earlier in this section. If the
tire pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-43.
3-64

SERVICE AIR BAG
This message displays if there is a problem with the
airbag system. Have your dealer/retailer inspect the
system for problems. SeeAirbag Readiness Light on
page 3-37andAirbag System on page 1-81for more
information.
SERVICE BATTERY CHARGING
SYSTEM
On some vehicles, this message displays if there is a
problem with the battery charging system. Under certain
conditions, the charging system light may also turn on in
the instrument panel cluster. SeeCharging System Light
on page 3-39. Driving with this problem could drain the
battery. Turn off all unnecessary accessories. Have the
electrical system checked as soon as possible. See your
dealer/retailer.
SERVICE BRAKE SYSTEM
This message displays along with the brake system
warning light if there is a problem with the brake system.
SeeBrake System Warning Light on page 3-40. 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 dealer/retailer.
SERVICE BRAKES SOON
This message displays if there is a problem with the
brake system. 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 dealer/retailer.
SERVICE PARK ASSIST
If your vehicle has the Ultrasonic Rear Parking Assist
(URPA) system, this message displays 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 2-53for more information. See your
dealer/retailer for service.
SERVICE SIDE BLIND ZONE ALERT
SYSTEM
If your vehicle has the Side Blind Zone Alert (SBZA)
system and this message displays, both SBZA displays
will remain on indicating there is a problem with the
SBZA system. If these displays remain on after
continued driving, the system needs service. See your
dealer/retailer. SeeSide Blind Zone Alert (SBZA)
on page 2-56for more information.
3-69

SERVICE STABILITRAK
If your vehicle has StabiliTrak®and this message
displays, it means there may be a problem with the
StabiliTrak system. If you see this message, try to
reset the system. Stop; turn off the engine for at least
15 seconds; then start the engine again. If this message
still comes on, it means there is a problem. You should
see your dealer/retailer for service. The vehicle is safe to
drive, however, you do not have the benet of StabiliTrak,
so reduce your speed and drive accordingly.
SERVICE SUSPENSION SYSTEM
If your vehicle has the Autoride®suspension system,
this message displays when the Autoride suspension
system is not operating properly. Have your vehicle
serviced by your dealer/retailer.
SERVICE THEFT DETERRENT SYSTEM
This message displays when there is a problem with
the theft-deterrent system. The vehicle may or may not
restart so you may want to take the vehicle to your
dealer/retailer before turning off the engine. See
PASS-Key
®III+ Electronic Immobilizer Operation on
page 2-23for more information.
SERVICE TIRE MONITOR SYSTEM
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays if a part on the TPMS is
not working properly. The tire pressure light also ashes
and then remains on during the same ignition cycle. See
Tire Pressure Light on page 3-43. Several conditions may
cause this message to appear. SeeTire Pressure Monitor
Operation on page 5-74for more information. If the
warning comes on and stays on, there may be a problem
with the TPMS. See your dealer/retailer.
SERVICE TRACTION CONTROL
If your vehicle has StabiliTrak, this message displays
when there is a problem with the Traction Control
System (TCS). When this message displays, the system
will not limit wheel spin. Adjust your driving accordingly.
See your dealer/retailer for service. SeeStabiliTrak
®
System on page 4-6for more information.
3-70

There are several conditions that can cause this
message to appear.
One condition is overheating, which could occur if
StabiliTrak activates continuously for an extended
period of time.
The message also displays if the brake system
warning light is on. SeeBrake System Warning
Light on page 3-40.
The message could display if the stability system
takes longer than usual to complete its diagnostic
checks due to driving conditions.
The message displays if an engine or vehicle
related problem has been detected and the vehicle
needs service. See your dealer/retailer.
The message also displays if the vehicle is shifted
into 4LO.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN GAS CAP
This message may display along with the check engine
light on the instrument panel cluster if the vehicle’s
fuel cap is not tightened properly. SeeMalfunction
Indicator Lamp on page 3-44. Reinstall the fuel cap fully.
SeeFilling the Tank on page 5-9. 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
this light and message off.
TIRE LEARNING ACTIVE
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the TPMS
is re-learning the tire positions on your vehicle. The tire
positions must be re-learned after rotating the tires
or after replacing a tire or sensor. SeeTire Inspection
and Rotation on page 5-78,Tire Pressure Monitor
System on page 5-72, andInflation - Tire Pressure on
page 5-70for more information.
3-72

Braking
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
SeeBrake System Warning Light on page 3-40.
Braking action involves perception time and reaction
time. Deciding to push the brake pedal is perception
time. Actually doing it is reaction time.
Average reaction time is about three-fourths of a
second. But that is only an average. It might be less
with one driver and as long as two or three seconds or
more with another. Age, physical condition, alertness,
coordination, and eyesight all play a part. So do alcohol,
drugs, and frustration. But even in three-fourths of a
second, a vehicle moving at 60 mph (100 km/h) travels
66 feet (20 m). That could be a lot of distance in an
emergency, so keeping enough space between
the vehicle and others is important.
And, of course, actual stopping distances vary greatly
with the surface of the road, whether it is pavement or
gravel; the condition of the road, whether it is wet, dry, or
icy; tire tread; the condition of the brakes; the weight of
the vehicle; and the amount of brake force applied.Avoid needless heavy braking. Some people drive
in spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This
is a mistake. The brakes might not have time to
cool between hard stops. The brakes will wear out
much faster with a lot of heavy braking. Keeping pace
with the traffic and allowing realistic following distances
eliminates a lot of unnecessary braking. That means
better braking and longer brake life.
If the engine ever stops while the vehicle is being
driven, brake normally but do not pump the brakes.
If the brakes are pumped, the pedal could get harder
to push down. If the engine stops, there will still be some
power brake assist but it will be used when the brake
is applied. Once the power assist is used up, it can
take longer to stop and the brake pedal will be harder
to push.
Adding non-dealer/non-retailer accessories can affect
vehicle performance. SeeAccessories and Modifications
on page 5-3.
4-4

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on. This is normal.
If there is a problem with
ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-42.
Along with ABS, the vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights come on
accompanied by a 10-second chime. The lights and
chime will come on each time the ignition is turned on
until the problem is repaired. See your dealer/retailer for
service.Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps receiving
updates on wheel speed and controls braking pressure
accordingly.
Remember: ABS does not change the time needed to
get a foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, there will not be enough time to apply
the brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
with ABS.
4-5

It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn the
system off if the vehicle is stuck in sand, mud, ice or
snow, and you want to “rock” the vehicle to attempt to
free it. It may also be necessary to turn off the system
when driving in extreme off-road conditions where high
wheel spin is required. SeeIf Your Vehicle is Stuck in
Sand, Mud, Ice, or Snow on page 4-31
Traction Control Operation
The traction control system is part of the StabiliTrak
system. Traction control limits wheel spin by reducing
engine power to the wheels (engine speed management)
and by applying brakes to each individual wheel
(brake-traction control) as necessary.
The traction control system is enabled automatically
when the vehicle is started. It will activate and the
StabiliTrak light will ash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If traction control is turned off, only the
brake-traction control portion of traction control will
work. The engine speed management will be disabled.
In this mode, engine power is not reduced automatically
and the driven wheels can spin more freely. This can
cause the brake-traction control to activate constantly.Notice:If the wheel(s) of one axle is allowed to spin
excessively while the StabiliTrak, ABS and brake
warning lights and any relevant DIC messages are
displayed, the transfer case could be damaged. The
repairs would not be covered by the vehicle warranty.
Reduce engine power and do not spin the wheel(s)
excessively while these lights and messages are
displayed.
The traction control system may activate on dry or rough
roads or under conditions such as heavy acceleration
while turning or abrupt upshifts/downshifts of the
transmission. When this happens, a reduction in
acceleration may be noticed, or a noise or vibration
may be heard. This is normal.
If cruise control is being used when the system activates,
the StabiliTrak light will ash and cruise control will
automatically disengage. Cruise control may be
reengaged when road conditions allow. SeeCruise
Control on page 3-12
StabiliTrak may also turn off automatically if it determines
that a problem exists with the system. If the problem does
not clear itself after restarting the vehicle, see your
dealer/retailer for service.
4-8

Driving in Rain and on Wet Roads
Rain and wet roads can reduce vehicle traction and affect
your ability to stop and accelerate. Always drive slower
in these types of driving conditions and avoid driving
through large puddles and deep-standing or owing
water.
{CAUTION:
Wet brakes can cause crashes. They might not
work as well in a quick stop and could cause
pulling to one side. You could lose control of the
vehicle.
After driving through a large puddle of water or a
car/vehicle wash, lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates strong forces.
Driving through owing water could cause your
vehicle to be carried away. If this happens, you
and other vehicle occupants could drown. Do not
ignore police warnings and be very cautious about
trying to drive through owing water.
Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they actually ride on the water. This
can happen if the road is wet enough and you are going
fast enough. When your vehicle is hydroplaning, it has
little or no contact with the road.
There is no hard and fast rule about hydroplaning. The
best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth. SeeTires
on page 5-62.
Turn off cruise control.
4-26