2008 GMC ACADIA brake

Brake System Warning Light
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, there is a brake problem.
Have your brake system inspected right away.
This light should come on briey when you turn the
ignition key to ON. If it does not come on then, have it
xed so it will be ready to warn you if there is a problem.
This light may also come on due to low brake uid.
SeeBrakes on page 5-35for more information.When the ignition is on, the brake system warning light
will also come on when you set your parking brake.
The light will stay on if your parking brake does
not release fully. If it stays on after your parking brake
is fully released, it means you have a brake problem.
If the light comes on while you are driving, pull off
the road and stop carefully. Make sure the parking brake
is fully released. You may notice that the pedal is
harder to push or, the pedal 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 4-26.
{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. United StatesCanada
3-47

Antilock Brake System
Warning Light
For vehicles with
the Antilock Brake
System (ABS), this
light will come on
briey when you
start the engine.
That is 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 ABS light stays on, turn the ignition off, if the light
comes on when you are 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 still
stays on, or comes on again while you are driving,
your vehicle needs service. If the regular brake system
warning light is not on, you still have brakes, but you
do not have antilock brakes. If the regular brake system
warning light is also on, you do not have antilock
brakes and there is a problem with your regular brakes.
SeeBrake System Warning Light on page 3-47
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-66for
all brake related DIC messages.
StabiliTrak®Indicator Light
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 4-6for more
information.
3-48

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.
ALL WHEEL DRIVE OFF
If your vehicle has the All-Wheel Drive (AWD) system,
this message displays when there is a compact
spare tire on the vehicle, when the Antilock Brake
System (ABS) warning light comes on, or when the
rear differential uid is overheating. This message
turns off when the differential uid cools.
The AWD system is disabled until the compact spare
tire is replaced by a full-size tire. If the warning message
is still on after putting on the full-size tire, you need to
reset the warning message. To reset the warning
message, turn the ignition off and then back on again
after 30 seconds. If the message stays on, see your
dealer/retailer right away. SeeAll-Wheel Drive (AWD)
System on page 4-9for more information.
AUTOMATIC LIGHT CONTROL OFF
This message displays when the automatic
headlamps are turned off. This message clears
itself after 10 seconds.
AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic
headlamps are turned on. This message clears
itself after 10 seconds.
3-66

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 3-42andAirbag System on page 1-61for
more information.
SERVICE ALL WHEEL DRIVE
If your vehicle has the All-Wheel Drive (AWD) system,
this message displays if there is a problem with this
system. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicle
after 30 seconds and check for the message on the
DIC display. If the message is still displayed or appears
again when you begin driving, the AWD system
needs service. See your dealer/retailer.
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 3-45. 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 3-47. 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 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 2-45for more information.
See your dealer/retailer for service.
SERVICE POWER STEERING
This message displays when a problem is detected
with the power steering system. When this message
is displayed, you may notice that the effort required to
steer the vehicle increases or feels heavier, but you
will still be able to steer the vehicle. Have your vehicle
serviced by your dealer/retailer immediately.
3-72

Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunk Driving.................................................4-2
Control of a Vehicle........................................4-3
Braking.........................................................4-4
Antilock Brake System (ABS)...........................4-5
Braking in Emergencies...................................4-6
StabiliTrak
®System........................................4-6
All-Wheel Drive (AWD) System.........................4-9
Steering........................................................4-9
Off-Road Recovery.......................................4-11
Passing.......................................................4-11
Loss of Control.............................................4-12
Driving at Night............................................4-13Driving in Rain and on Wet Roads..................4-14
Before Leaving on a Long Trip.......................4-15
Highway Hypnosis........................................4-15
Hill and Mountain Roads................................4-16
Winter Driving..............................................4-17
If Your Vehicle is Stuck in Sand, Mud, Ice,
or Snow...................................................4-20
Rocking Your Vehicle to Get It Out.................4-21
Loading Your Vehicle....................................4-21
Towing..........................................................4-26
Towing Your Vehicle.....................................4-26
Recreational Vehicle Towing...........................4-26
Towing a Trailer...........................................4-30
Section 4 Driving Your Vehicle
4-1

Death and injury associated with drinking and driving is
a global tragedy.
Alcohol affects four things that anyone needs to drive a
vehicle: judgment, muscular coordination, vision, and
attentiveness.
Police records show that almost 40 percent of all motor
vehicle-related deaths involve alcohol. In most cases,
these deaths are the result of someone who was
drinking and driving. In recent years, more than
17,000 annual motor vehicle-related deaths have been
associated with the use of alcohol, with about
250,000 people injured.
For persons under 21, it is against the law in every U.S.
state to drink alcohol. There are good medical,
psychological, and developmental reasons for
these laws.
The obvious way to eliminate the leading highway
safety problem is for people never to drink alcohol and
then drive.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 your 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 your
vehicle. SeeStabiliTrak
®System on page 4-6.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-4.
4-3

Braking
SeeBrake System Warning Light on page 3-47.
Braking action involves perception time and reaction
time. First, you have to decide to push on the brake
pedal. That is perception time. Then you have to bring
up your foot and do it. That 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
your 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 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 vehicle’s engine ever stops while you are driving,
brake normally but do not pump the brakes. If you do,
the pedal could get harder to push down. If the
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 can take longer to stop and
the brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affect
your vehicle’s performance. SeeAccessories and
Modifications on page 5-4.
4-4

Antilock Brake System (ABS)
Your vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
prevent a braking skid.
When you start the engine and begin to drive away,
ABS will check itself. You might hear a momentary
motor or clicking noise while this test is going on, and
you might even notice that the brake pedal moves
a little. This is normal.
If there is a problem with
ABS, this warning light will
stay on. SeeAntilock
Brake System Warning
Light on page 3-48.
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 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 faster than any
driver could. The computer is programmed to make the
most of available tire and road conditions. This can
help you steer around the obstacle while braking hard.
As you brake, the computer keeps receiving updates
on wheel speed and controls braking pressure
accordingly.
Remember: ABS 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 the brakes if
that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you
have ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work for you. You might hear
the antilock pump or motor operate, and feel the
brake pedal pulsate, but this is normal.
4-5