2005 GMC YUKON brake light

Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light doesn’t come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you’re driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
The traction off light may come on for the following
reasons:
If you turn the system off by pressing the TAS
on/off button located to the left of the steering wheel,
the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.
If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation.
To turn the system back on, move the shift lever
back to a position other than FIRST (1); the
light should go off. SeeTraction Assist System
(TAS) on page 4-8.
The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, seeTraction Assist
System (TAS) on page 4-8.
If the Traction Assist System is affected by an
anti-lock brake system, TAS or engine-related
problem, the system will turn off and the light will
come on. Have your vehicle serviced.
If the vehicle is driven over an extremely rough road,
the system will turn off and the light will come on. The
light will go off a few seconds after the rough road
conditions go away or when the vehicle comes to a
complete stop. This is normal operation.
3-45

SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this message
will be displayed on the DIC. 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. Pressing any of the four DIC
buttons, if equipped, will acknowledge the message and
clear it from the DIC display. If your vehicle is not
equipped with the four DIC buttons, pressing the trip
odometer reset stem will acknowledge the message and
clear it from the DIC display.
SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the DIC.
Under certain conditions, the battery warning light may
also turn on in the instrument panel cluster. SeeBattery
Warning Light on page 3-42. The battery will not be
charging at an optimal rate and the vehicle will lose the
ability to enter the fuel economy mode. The vehicle is
safe to drive, however you should have the electrical
system checked by your GM dealer. Pressing any of the
four DIC buttons, if equipped, will acknowledge the
message and clear it from the DIC display. If your vehicle
is not equipped with the four DIC buttons, pressing the
trip odometer reset stem will acknowledge the message
and clear it from the DIC display.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If the message appears
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
ride control needs service. See your GM dealer. Pressing
any of the four DIC buttons, if equipped, will acknowledge
the message and clear it from the DIC display. If your
vehicle is not equipped with the four DIC buttons,
pressing the trip odometer reset stem will acknowledge
the message and clear it from the DIC display.
SERVICE STABILITY
If you ever see the SERVICE STABILITY message,
it means there may be a problem with your
StabiliTrak
®system. If you see this message, try to reset
the system. Stop; turn off the engine; then start the
engine again. If the SERVICE STABILITY message still
comes on, it means there is a problem. You should see
your GM dealer for service. The vehicle is safe to drive,
however, you do not have the benet of StabiliTrak
®,so
reduce your speed and drive accordingly. Pressing any of
the four DIC buttons, if equipped, will acknowledge the
message and clear it from the DIC display. If your vehicle
is not equipped with the four DIC buttons, pressing the
trip odometer reset stem will acknowledge the message
and clear it from the DIC display.
3-65

SERVICE TIRE MONITOR
If your vehicle is equipped with the Tire Pressure Monitor
System, this message will be displayed if one or more of
the tire monitor sensors have malfunctioned or if all of the
tire monitor sensors have not been programmed
successfully. See your GM dealer. Pressing any of the
four DIC buttons, if equipped, will acknowledge the
message and clear it from the DIC display. If your vehicle
is not equipped with the four DIC buttons, pressing the
trip odometer reset stem will acknowledge the message
and clear it from the DIC display. The message will
reappear at each ignition cycle until the system has been
serviced.
STABILITY SYS ACTIVE
You may see the STABILITY SYS ACTIVE message on
the DIC. It means that an advanced computer-controlled
system has come on to help your vehicle continue to
go in the direction in which you are steering.
StabiliTrak
®activates when the computer senses that
your vehicle is just starting to spin, as it might if you hit a
patch of ice or other slippery spot on the road. When
the system activates, you may hear a noise or feel
a vibration in the brake pedal. This is normal. When the
STABILITY SYS ACTIVE message is on, you should
continue to steer in the direction you want to go.
The system is designed to help you in bad weather or
other difficult driving situations by making the most
of whatever road conditions will permit.
STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the StabiliTrak®button or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full benets of the stability
enhancement system, you should normally leave
StabiliTrak
®on. However, you should turn
StabiliTrak®off if your vehicle gets stuck in sand, mud,
ice or snow and you want to “rock” your vehicle to attempt
to free it, or if you are driving in extreme off-road
conditions and require more wheel spin. SeeIf Your
Vehicle is Stuck in Sand, Mud, Ice or Snow on page 4-49.
To turn the StabiliTrak
®system back on, press the
StabiliTrak®button again.
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 will also be displayed if the brake
system warning light is on. SeeBrake System
Warning Light on page 3-43.
The message could be displayed if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
3-66

If an engine or vehicle related problem has been
detected and the vehicle needs service, the
message will appear. See your GM dealer.
The message will also appear if the vehicle is
shifted into 4LO.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel. SeeMalfunction Indicator Lamp
on page 3-48. Reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 5-8. The
diagnostic system can determine if the fuel cap has been
left off or improperly installed. A loose or missing fuel cap
will allow fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should turn the
light and message off.
TRACTION ACTIVE
When the traction control system has detected that any
of the vehicle’s wheels are spinning, the traction
control system will activate and this message will appear
on the DIC. For more information, seeTraction Assist
System (TAS) on page 4-8.
TRACTION SYS LIMITED
If the brake traction control system activates constantly
or if the brakes have heated up due to high-speed
braking, brake traction control will be displayed and the
TRACTION SYS LIMITED message will be displayed.
The system will return to normal operation after the
brakes have cooled.
TRANS HOT IDLE ENGINE
If the transmission uid in the vehicle gets hot, this
message will appear on the DIC and you will hear a
chime. The chime will stop when the transmission uid
temperature is less that 265°F (129°C). Driving with
the transmission uid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message will
clear when the uid temperature reaches a safe level.
SeeTransmission Temperature Gage on page 3-46.
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed on
the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead to
costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while transmission
temperature warning is displayed.
3-67

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. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.Anti-Lock Brake System (ABS)
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-44.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will 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 for service.
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Remember: Anti-lock does not change the time you
need to get your foot up to the brake pedal or always
decrease stopping distance. If you get too close to
the vehicle in front of you, you will not have time to apply
your brakes if that vehicle suddenly slows or stops.
Always leave enough room up ahead to stop, even
though you have anti-lock brakes.
Using Anti-Lock
Do not pump the brakes. Just hold the brake pedal
down rmly and let anti-lock work for you. You may feel
the brakes vibrate, or you may notice some noise,
but this is normal.
Braking in Emergencies
With anti-lock brakes, you can steer and brake at the
same time. In many emergencies, steering can help you
more than even the very best braking.
Traction Assist System (TAS)
Your vehicle may have a Traction Assist System (TAS)
that limits wheel spin. This is especially useful in
slippery road conditions. The system operates only if it
senses that one or both of the rear wheels are
spinning or beginning to lose traction. When this
happens, the system reduces engine power to limit
wheel spin.The traction control system is enabled every time your
vehicle is started. The system will activate if it senses
that any of the wheels are spinning or beginning to lose
traction.
You may hear or feel the system working or notice a
lack of accelerator response, but this is normal.
The Traction Assist System may operate on dry roads
under some conditions. When this happens, you
may notice a reduction in acceleration. This is normal
and doesn’t mean there’s a problem with your vehicle.
Examples of these conditions include a hard
acceleration in a turn, an abrupt upshift or downshift of
the transmission or driving on rough roads.
If your vehicle is in cruise control when the TAS begins
to limit wheel spin, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may re-engage the cruise control.
SeeCruise Control on page 3-11.
When the traction off light
is on, the TAS is off and
will not limit wheel
spin. Adjust your driving
accordingly.
4-8

The traction off light will come on under the following
conditions:
The Traction Assist System is turned off, either by
pressing the TAS on/off button or turning off the
automatic engagement feature of the TAS.
The transmission is in FIRST (1); TAS will not
operate in this gear. This is normal.
The vehicle is driven on an extremely rough road.
When the vehicle leaves the rough surface, slows
down or stops, the light will go off and TAS will
be on again. This is normal.
A Traction Assist System, Anti-Lock Brake System
or engine-related problem has been detected and
the vehicle needs service.
If the vehicle has been driven with the TAS system
on for long periods of time, or if the vehicle has
gone through many high speed braking maneuvers
the system may be automatically disabled. The
system will automatically re-enable after
approximately two minutes of not using the brakes.
The Traction Assist System, as delivered from the
factory, will automatically come on whenever you start
your vehicle. To limit wheel spin, especially in
slippery road conditions, you should always leave the
system on. But you can turn the TAS off if you ever need
to. You should turn the TAS off if your vehicle evergets stuck in sand, mud or snow and rocking the vehicle
is required. SeeRocking Your Vehicle to Get It Out
on page 4-50.
To turn the system on or
off, press the TAS on/off
button located on the
instrument panel.
If you used the button to turn the system off, the traction
off light will come on and stay on. You can turn the
system back on at any time by pressing the button
again. The traction off light should go off.
If desired, you can change the TAS automatic
engagement feature so that the system will not come on
automatically when the engine is started. To do so:
1. Park the vehicle with the ignition off and the
transmission in PARK (P).
2. Turn the ignition to RUN; do not start the engine.
4-9

The StabiliTrak®button is
located on the instrument
panel.
StabiliTrak
®and part of the traction control system can
be turned off or back on by pressing the StabiliTrak®
button. All-wheel drive vehicles must be in all-wheel
drive mode to turn the system on or off.
Four-wheel-drive vehicles must be in 2HI, 4HI
or AUTO 4WD to turn the system on or off.
When the system is turned off, the traction off light will
illuminate, and the STABILITY SYS DISABLED
message will appear on the DIC to warn the driver that
both the stability system and part of the traction
control system are disabled. Your vehicle will still have
brake-traction control when StabiliTrak
®is off, but
will not be able to use the engine speed management
system. See “Traction Control Operation” next for
more information.
When the StabiliTrak
®system has been turned off, you
may still hear system noises as a result of the
brake-traction control coming on.It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn the
system off if your vehicle is stuck in sand, mud, ice or
snow, and you want to “rock” your 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 4-49.
When the transfer case is in 4LO, the stability system is
automatically disabled, and the STABILITY SYS
DISABLED message will appear on the DIC. In 4LO,
the StabiliTrak
®button only turns the traction control
system on and off.
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 you start your vehicle, and it will activate
and display the TRACTION ACTIVE message in the
Driver Information Center (DIC) if it senses that any of
the wheels are spinning or beginning to lose traction
while driving. If you turn off StabiliTrak
®, only the
brake-traction control portion of traction control will work.
4-11