2007 GMC ACADIA light

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 337.
Adding non-dealer/non-retailer accessories can
affect your vehicle’s performance. SeeAccessories
and Modifications on page 385.
Braking
SeeBrake System Warning Light on page 222.
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.
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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 385.
Anti-Lock Brake System (ABS)
Your vehicle has the Anti-Lock 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.
SeeAnti-Lock Brake
System Warning
Light on page 223.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.
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StabiliTrak®System
Your 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 rst start your vehicle and begin to
drive away, the system performs several
diagnostic checks to ensure there are no
problems. You may hear or feel the system
working. This is normal and does not mean
there is a problem with your vehicle. The system
should initialize before the vehicle reaches
20 mph (32 km/h). In some cases, it may take
approximately two miles of driving before the
system initializes.
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 you see these
conditions, 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), your vehicle should
be taken in for service. For more information on
the DIC messages, seeDriver Information
Center (DIC) on page 232.
The StabiliTrak
®light
will ash on the
instrument panel cluster
when the system is
both on and activated.
You may also feel or hear the system 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.
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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. Your 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, 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 360.
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. 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 you turn off traction control, 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 you allow the wheel(s) of one axle
to spin excessively while the StabiliTrak
®,
ABS and brake warning lights and the SERVICE
STABILITRAK message are displayed, you
could damage the transfer case. The repairs
would not be covered by your warranty.
Reduce engine power and do not spin the
wheel(s) excessively while these lights and this
message are displayed.
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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, you may notice a reduction
in acceleration, or may hear a noise or vibration.
This is normal.
If your vehicle is in cruise control when the system
activates, the StabiliTrak
®light will ash and the
cruise control will automatically disengage.
When road conditions allow you to use cruise
again, you may re-engage the cruise control.
SeeCruise Control on page 180.
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, you should see your dealer/retailer
for service.
All-Wheel Drive (AWD) System
If your 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 front axle. It is fully automatic, and
adjusts itself as needed for road conditions.
When using a compact spare tire on your 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 clutch in your AWD system, replace the
compact spare with a full-size tire as soon as
possible. SeeCompact Spare Tire on page 477
for more information.
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Off-Road Recovery
You may nd that your vehicle’s right wheels have
dropped off the edge of a road onto the shoulder
while you are 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 nothingin the way, steer so that your vehicle straddles the
edge of the pavement. You can turn the steering
wheel up to one-quarter turn until the right front tire
contacts the pavement edge. Then turn the steering
wheel to go straight down the roadway.
Passing
The driver of a vehicle about to pass another on a
two-lane highway waits for just the right moment,
accelerates, moves around the vehicle ahead,
then goes back into the right lane again. A simple
maneuver?
Not necessarily! Passing another vehicle on a
two-lane highway is a potentially dangerous move,
since the passing vehicle occupies the same
lane as oncoming traffic for several seconds.
A miscalculation, an error in judgment, or a brief
surrender to frustration or anger can suddenly
put the passing driver face to face with the worst
of all traffic accidents — the head-on collision.
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Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to
be impaired — by alcohol or drugs, with night
vision problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
Do not drink and drive.
Adjust the inside rearview mirror to reduce the
glare from headlamps behind you.
Since you cannot see as well, slow down and
keep more space between you and other
vehicles.
Slow down, especially on higher speed roads.
Your vehicle’s headlamps can light up only so
much road ahead.
In remote areas, watch for animals.
If you are tired, pull off the road in a safe
place and rest.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 require at least twice as
much light to see the same thing at night as a
20-year-old.
What you do in the daytime can also affect your
night vision. For example, if you spend the
day in bright sunshine you are wise to wear
sunglasses. Your eyes will have less trouble
adjusting to night. But if you are driving, do not
wear sunglasses at night. They might cut down on
glare from headlamps, but they also make a lot
of things invisible.
You can be temporarily blinded by approaching
headlamps. It can take a second or two, or
even several seconds, for your eyes to re-adjust
to the dark. When you are faced with severe glare,
as from a driver who does not lower the high
beams, or a vehicle with misaimed headlamps,
slow down a little. Avoid staring directly into
the approaching headlamps.
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Keep the windshield and all the glass on your
vehicle clean — inside and out. Glare at night is
made much worse by dirt on the glass. Even the
inside of the glass can build up a lm caused
by dust. Dirty glass makes lights dazzle and ash
more than clean glass would, making the pupils
of your eyes contract repeatedly.
Remember that the headlamps light up far less of
a roadway when you are in a turn or curve.
Keep your eyes moving; that way, it is easier to
pick out dimly lighted objects. Just as the
headlamps should be checked regularly for
proper aim, so should your eyes be examined
regularly. Some drivers suffer from night
blindness — the inability to see in dim light — and
are not even aware of it.Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble.
On a wet road, you cannot stop, accelerate, or
turn as well because your vehicle’s tire-to-road
traction is not as good as on dry roads.
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