2007 GMC ACADIA brake

If this occurs, URPA assumes the object is still
attached, so you will have to wait until the
vehicle is driven forward above 15 mph
(25 km/h) before URPA will return to normal
operation.
The ultrasonic sensors need to be kept clean.
So, be sure to keep your vehicle’s rear bumper
free of mud, dirt, snow, ice, and slush. For
cleaning instructions, seeWashing Your
Vehicle on page 482. If the DIC still displays the
PARK ASSIST OFF message after cleaning the
bumper and driving forward at a speed of at
least 15 mph (25 km/h), see your dealer/retailer.
Other conditions that may affect system
performance include vibrations from a
jackhammer or the compression of air brakes
on a very large truck or other mechanical
devices that interfere with URPA performance.
As always, drivers should use care when backing
up a vehicle. Always look behind you, being
sure to check for other vehicles, obstructions
and blind spots.
If the vehicle bumper is damaged, the URPA
system may not work properly. Take the vehicle
to your dealer/retailer to repair the system.
Accessory Power Outlet(s)
The accessory power outlets can be used to
connect electrical equipment such as a cellular
phone or CB radio.
Your vehicle may have four accessory power
outlets. They are located on the instrument panel
below the climate controls, inside the front
center console storage bin, at the rear of the
center console, and in the rear cargo area.
To use the outlets, remove the cover. When not in
use, always cover the outlet with the protective cap.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always
turn off electrical equipment when not in
use and do not plug in equipment that exceeds
the maximum amperage rating of 20 amperes.
197

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 421for 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 367.
{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
222

Anti-Lock Brake System
Warning Light
Your vehicle has the Anti-Lock Brake System (ABS).
This light will come on
when your engine is
started and may stay
on for several seconds.
This is normal.
If the light stays on, turn the ignition to off.
If the light comes on and the chime sounds
when you are driving, pull your vehicle over to a
safe location and stop as soon as possible.Turn the ignition off. Then start the engine again
to reset the system. If the 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 anti-lock brakes.
If the regular brake system warning light is also
on, you do not have anti-lock brakes and there
is a problem with your regular brakes. SeeBrake
System Warning Light on page 222earlier in
this section.
The ABS warning light will come on briey when
you turn the ignition key to ON. This 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.
223

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 Anti-lock 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 339for more information.
AUTOMATIC LIGHT CONTROL OFF
This message displays when the automatic
headlamps are turned off. This message clears
itself after 10 seconds.
244

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 220.
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 222. 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. See
Ultrasonic Rear Parking Assist (URPA) on
page 194for 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.
251

Your Driving, the Road, and
Your Vehicle............................................ 330
Defensive Driving...................................... 330
Drunken Driving........................................ 331
Control of a Vehicle.................................. 334
Braking...................................................... 334
Anti-Lock Brake System (ABS).................. 335
Braking in Emergencies............................. 336
StabiliTrak
®System................................... 337
All-Wheel Drive (AWD) System.................. 339
Steering.................................................... 340
Off-Road Recovery.................................... 342
Passing..................................................... 342
Loss of Control.......................................... 344
Driving at Night......................................... 346Driving in Rain and on Wet Roads............ 347
City Driving............................................... 350
Freeway Driving........................................ 351
Before Leaving on a Long Trip.................. 352
Highway Hypnosis..................................... 353
Hill and Mountain Roads........................... 354
Winter Driving........................................... 356
If Your Vehicle is Stuck in Sand, Mud,
Ice, or Snow.......................................... 360
Rocking Your Vehicle to Get It Out........... 361
Loading Your Vehicle................................ 361
Towing........................................................ 367
Towing Your Vehicle................................. 367
Recreational Vehicle Towing...................... 367
Towing a Trailer........................................ 371
Section 4 Driving Your Vehicle
329

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.
334

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.
335