brake light GMC ACADIA 2009 User Guide

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 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. SeeStabiliTrak
®System on
page 4-5.
Adding non-dealer/non-retailer
accessories can affect vehicle
performance. SeeAccessories and
Modifications on page 5-3.
Braking
SeeBrake System Warning Light
on page 3-38.
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.
Driving Your Vehicle 4-3

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.
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,
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. See
Antilock Brake System (ABS)
Warning Light on page 3-39.
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 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.
4-4 Driving Your Vehicle

If the system fails to turn on or
activate, the StabiliTrak light along
with one of the following messages
will be displayed on the Driver
Information Center (DIC):
TRACTION CONTROL OFF,
SERVICE TRACTION CONTROL,
SERVICE STABILITRAK. 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,
seeDriver Information Center (DIC)
on page 3-46.
The StabiliTrak light will ash 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 disable button
is located on the instrument
panel below the climate controls.
The traction control part of
StabiliTrak can be turned off by
pressing and releasing the traction
control disable button.
Traction control can be turned on
by pressing and releasing the
traction control disable button if
not automatically shut off for any
other reason.
When the traction control system is
turned off, the StabiliTrak light and
the appropriate traction control off
message will be displayed on the
DIC to warn the driver. 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” next 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. SeeIf Your
Vehicle is Stuck in Sand, Mud,
Ice, or Snow on page 4-15.
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.
4-6 Driving Your Vehicle

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 3-9.
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.All-Wheel Drive (AWD)
System
If the vehicle has this feature,
engine power is sent to all four
wheels when extra traction is
needed. This is like four-wheel drive,
but there is no separate lever or
switch to engage or disengage the
axle. It is fully automatic, and
adjusts itself as needed for road
conditions.
When using a compact spare tire
on the AWD equipped vehicle,
the AWD system automatically
detects the presence of the compact
spare and the AWD is disabled.
To restore the AWD operation and
prevent excessive wear on the
AWD system, replace the compact
spare with a full-size tire as
soon as possible. SeeCompact
Spare Tire on page 5-81for more
information.
Driving Your Vehicle 4-7

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.Ease off the accelerator and then, if
there is nothing in the way, steer
so that the vehicle straddles
the edge of the pavement. Turn
the steering wheel 3 to 5 inches,
8 to 13 cm, (about one-eighth turn)
until the right front tire contacts
the pavement edge. Then turn
the steering wheel to go straight
down the roadway.Passing
Passing another vehicle on a
two-lane road can be dangerous.
To reduce the risk of danger
while passing:
Look down the road, to the sides,
and to crossroads for situations
that might affect a successful
pass. If in doubt, wait.
Watch for traffic signs, pavement
markings, and lines that could
indicate a turn or an intersection.
Never cross a solid or
double-solid line on your
side of the lane.
Do not get too close to the vehicle
you want to pass. Doing so can
reduce your visibility.
Wait your turn to pass a slow
vehicle.
When you are being passed, ease
to the right.
Loss of Control
Let us review what driving experts
say about what happens when
the three control systems — brakes,
steering, and acceleration — do
not have enough friction where the
tires meet the road to do what
the driver has asked.
In any emergency, do not give up.
Keep trying to steer and constantly
seek an escape route or area of
less danger.
Driving Your Vehicle 4-9

Skidding
In a skid, a driver can lose control
of the vehicle. Defensive drivers
avoid most skids by taking
reasonable care suited to existing
conditions, and by not overdriving
those conditions. But skids are
always possible.
The three types of skids correspond
to the vehicle’s three control
systems. In the braking skid, the
wheels are not rolling. In the steering
or cornering skid, too much speed
or steering in a curve causes tires
to slip and lose cornering force.
And in the acceleration skid, too
much throttle causes the driving
wheels to spin.
If the vehicle starts to slide, ease
your foot off the accelerator
pedal and quickly steer the way you
want the vehicle to go. If you
start steering quickly enough, the
vehicle may straighten out. Always
be ready for a second skid if it
occurs.Of course, traction is reduced when
water, snow, ice, gravel, or other
material is on the road. For safety,
slow down and adjust your
driving to these conditions. It is
important to slow down on slippery
surfaces because stopping
distance is longer and vehicle
control more limited.
While driving on a surface with
reduced traction, try your best to
avoid sudden steering, acceleration,
or braking, including reducing vehicle
speed by shifting to a lower gear.
Any sudden changes could cause
the tires to slide. You might not
realize the surface is slippery until
the vehicle is skidding. Learn to
recognize warning clues — such as
enough water, ice, or packed snow
on the road to make a mirrored
surface — and slow down when you
have any doubt.
Remember: Any Antilock Brake
System (ABS) helps avoid only the
braking skid.
Driving at Night
Night driving is more dangerous than
day driving because some drivers
are likely to be impaired — by alcohol
or drugs, with night vision problems,
or by fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by
adjusting the inside rearview
mirror.
Slow down and keep more space
between you and other vehicles
because headlamps can only
light up so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into
approaching headlamps.
4-10 Driving Your Vehicle

Keep the windshield and all glass
on your vehicle clean — inside
and out.
Keep your eyes moving,
especially during turns or curves.
No one can see as well at night as
in the daytime. But, as we get
older, these differences increase.
A 50-year-old driver might need
at least twice as much light to see
the same thing at night as a
20-year-old.
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 5-35.
Turn off cruise control.
Driving Your Vehicle 4-11

Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located
at the rear of the vehicle and is
tied to the vehicle’s frame.
The harness connector can be
plugged into a seven-pin universal
heavy-duty trailer connector
available through your
dealer/retailer.
The seven-wire harness contains
the following trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn
Signal
Brown: Taillamps
Black: Ground
Light Green: Back-up Lamps
Red/Black: Battery Feed
Dark Blue: Trailer Brake*
*The fuse for this circuit is installed
in the underhood electrical center,
but the wires are not connected.
They should be connected by your
dealer/retailer or a qualied
service center.
If the back-up lamp circuit is not
functional, contact your
dealer/retailer.If a remote (non-vehicle) battery is
being charged, press the Tow/Haul
mode switch located on the center
console near the climate controls.
This will boost the vehicle system
voltage and properly charge the
battery. If the trailer is too light for
Tow/Haul mode, turn on the
headlamps (Non-HID only) as a
second way to boost the vehicle
system and charge the battery.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. SeeEngine Overheating
on page 5-21.
Driving Your Vehicle 4-33

Brakes
Brake Fluid
The brake master cylinder reservoir
is lled with DOT-3 brake uid.
SeeEngine Compartment Overview
on page 5-10for the location of
the reservoir.There are only two reasons why the
brake uid level in the reservoir
might go down:
The brake uid level goes down
because of normal brake lining
wear. When new linings are
installed, the uid level goes
back up.
A uid leak in the brake hydraulic
system can also cause a low uid
level. Have the brake hydraulic
system xed, since a leak means
that sooner or later the brakes will
not work well.
Do not top off the brake uid.
Adding uid does not correct a leak.
If uid is added when the linings are
worn, there will be too much uid
when new brake linings are installed.
Add or remove brake uid, as
necessary, only when work is done
on the brake hydraulic system.
{CAUTION
If too much brake uid is added, it
can spill on the engine and burn, if
the engine is hot enough. You or
others could be burned, and the
vehicle could be damaged. Add
brake uid only when work is done
on the brake hydraulic system.
When the brake uid falls to a low
level, the brake warning light comes
on. SeeBrake System Warning
Light on page 3-38.
Service and Appearance Care 5-25

Some driving conditions or climates
can cause a brake squeal when the
brakes are rst applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specications inCapacities and
Specifications on page 5-96.
Brake linings should always be
replaced as complete axle sets.Brake Pedal Travel
See your dealer/retailer if the brake
pedal does not return to normal
height, or if there is a rapid increase
in pedal travel. This could be a sign
that brake service might be required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designedand tested with top-quality brake
parts. When parts of the braking
system are replaced — for example,
when the brake linings wear down
and new ones are installed — be
sure to get new approved
replacement parts. If this is not
done, the brakes might not work
properly. For example, if someone
puts in brake linings that are wrong
for the vehicle, the balance between
the front and rear brakes can
change — for the worse. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed.
Service and Appearance Care 5-27