2011 GMC ACADIA brake light

Black plate (3,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-3
Medical research shows that
alcohol in a person's system
can make crash injuries worse,
especially injuries to the brain,
spinal cord, or heart. This means
that when anyone who has been
drinking—driver or passenger —is
in a crash, that person's chance of
being killed or permanently disabled
is higher than if the person had not
been drinking.
Control of a Vehicle
The following three systems
help to control the vehicle while
driving —brakes, steering, and
accelerator. At times, as when
driving on snow or ice, it is easy to
ask more of those control systems
than the tires and road can provide.
Meaning, you can lose control of the
vehicle. See StabiliTrak
®System on
page 9‑31.
Adding non‐dealer accessories
can affect vehicle performance.
See Accessories and Modifications
on page 10‑3.
Braking
See Brake System Warning Light on
page 5‑20.
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
100 km/h (60 mph) travels 20 m
(66 ft). 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.

Black plate (5,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-5
Steering in Emergencies
There are times when steering
can be more effective than braking.
For example, you come over a hill
and find a truck stopped in your
lane, or a car suddenly pulls out
from nowhere, or a child darts out
from between parked cars and stops
right in front of you. These problems
can be avoided by braking—if you
can stop in time. But sometimes you
cannot stop in time because there
is no room. That is the time for
evasive action —steering around
the problem.
The vehicle can perform very
well in emergencies like these.
First apply the brakes. See Braking
on page 9‑3. It is better to remove
as much speed as possible from
a collision. Then steer around
the problem, to the left or right
depending on the space available.
An emergency like this requires
close attention and a quick decision.
If holding the steering wheel at
the recommended 9 and 3 o'clock
positions, it can be turned a full
180 degrees very quickly without
removing either hand. But you have
to act fast, steer quickly, and just as
quickly straighten the wheel once
you have avoided the object.
The fact that such emergency
situations are always possible is a
good reason to practice defensive
driving at all times and wear safety
belts properly.
Off-Road Recovery
The vehicle's right wheels can drop
off the edge of a road onto the
shoulder while driving.
If the level of the shoulder is
only slightly below the pavement,
recovery should be fairly easy.

Black plate (7,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-7
Driving 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 flowing water.
{WARNING
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.(Continued)
WARNING (Continued)
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
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 flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the 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 the 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 fluid
reservoir filled.
.Have good tires with proper
tread depth. See
Tires on
page 10‑38.
.Turn off cruise control.

Black plate (29,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-29
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock
Brake System (ABS), an advanced
electronic braking system that helps
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, and it might
even be noticed that the brake
pedal moves a little. This is normal.
If there is a problem with ABS, this
warning light stays on. SeeAntilock
Brake System (ABS) Warning Light
on page 5‑21. If driving safely on a wet road and
it becomes necessary to slam on
the brakes and continue braking
to avoid a sudden obstacle, 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 wheel.
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.
Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You might hear the ABS
pump or motor operating and feel
the brake pedal pulsate, but this is
normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.

Black plate (30,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-30 Driving and Operating
Parking Brake
To set the parking brake, hold the
regular brake pedal down, then
push the parking brake pedal down.
If the ignition is on, the brake
system warning light will come on.
SeeBrake System Warning Light on
page 5‑20. Notice:
Driving with the parking
brake on can overheat the brake
system and cause premature
wear or damage to brake system
parts. Make sure that the parking
brake is fully released and the
brake warning light is off before
driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the park brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will be on and
a chime will sound warning you that
the parking brake is still on.
If you are towing a trailer and
are parking on a hill, see Driving
Characteristics and Towing Tips on
page 9‑47.
Brake Assist
This vehicle has a brake assist
feature designed to assist the
driver in stopping or decreasing
vehicle speed in emergency
driving conditions. This feature
uses the stability system hydraulic
brake control module to supplement
the power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle.
The stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time
is normal and the driver should
continue to apply the brake pedal
as the driving situation dictates.
The brake assist feature will
automatically disengage when
the brake pedal is released or
brake pedal pressure is quickly
decreased.

Black plate (31,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-31
Ride Control Systems
StabiliTrak®System
The vehicle has the StabiliTrak
system which combines antilock
brake, traction and stability control
systems and helps the driver
maintain directional control of the
vehicle in most driving conditions.
When you first start the vehicle
and begin to drive away, the
system performs several diagnostic
checks to ensure there are no
problems. The system may be
heard or felt while it is working.
This is normal and does not
mean there is a problem with the
vehicle. The system should initialize
before the vehicle reaches 32 km/h
(20 mph). In some cases, it may
take approximately 3.2 km (2 miles)
of driving before the system
initializes.
If the system fails to turn on or
activate, one of the following
messages will be displayed on theDriver Information Center (DIC):
SERVICE TRACTION CONTROL,
SERVICE STABILITRAK, the
StabiliTrak light will come on
and stay and four chimes are
heard. If these conditions are
observed, turn the vehicle off, wait
15 seconds, and then turn it back
on again to reset the system. If any
of these messages still appear on
the Driver Information Center (DIC),
the vehicle should be taken in for
service. For more information on
the DIC messages, see
Driver
Information Center (DIC) (With DIC
Buttons) on page 5‑25 orDriver
Information Center (DIC) (Without
DIC Buttons) on page 5‑30.
The StabiliTrak light will flash on the
instrument panel cluster when the
system is both on and activated. The system may be heard or felt
while it is working; this is normal.
The traction control button is located
on the instrument panel.
The traction control part of
StabiliTrak can be turned off by
pressing and releasing the traction
control button.
Traction control can be turned
on by pressing and releasing the
traction control button and the
appropriate TRACTION CONTROL
ON message will be displayed, if not
automatically shut off for any other
reason.

Black plate (32,1)GMC Acadia/Acadia Denali Owner Manual - 2011
9-32 Driving and Operating
When the traction control system
is turned off, the appropriate
TRACTION CONTROL OFF
message will be displayed on
the DIC. The vehicle will still
have brake-traction control when
traction control is off, but will not
be able to use the engine speed
management system. See“Traction
Control Operation” following for
more information.
When the traction control system
has been turned off, system noises
may be heard and felt as a result of
the brake-traction control working.
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. See If the Vehicle is
Stuck on page 9‑11.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 the brakes as necessary.
The traction control system is
enabled automatically when the
vehicle is started. It will activate
and the StabiliTrak light will flash
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, 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.

Black plate (33,1)GMC Acadia/Acadia Denali Owner Manual - 2011
Driving and Operating 9-33
If cruise control is being used when
the system activates, the StabiliTrak
light will flash and cruise control will
automatically disengage. Cruise
control may be reengaged when
road conditions allow. SeeCruise
Control on page 9‑33.
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 for service.Cruise Control
With cruise control, a speed of
about 40 km/h (25 mph) or more
can be maintained without keeping
your foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
When the brakes are applied, the
cruise control is disengaged.
{WARNING
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. So, do not use
the cruise control on winding
roads or in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.The cruise control buttons are
located on left side of the steering
wheel.
T(On/Off): Press to turn cruise
control on and off. The indicator
comes on when cruise control is on.
+ RES (Resume/Accelerate):
Press briefly to make the vehicle
resume to a previously set speed,
or press and hold to accelerate.
SET– :Press to set the speed and
activate cruise control or to make
the vehicle decelerate.