2007 GMC ACADIA parking brake

The system does not work at a reverse speed
greater than 5 mph (8 km/h). To remind you of this,
the red light on the rear display will ash.
To disable URPA, seeDIC Operation and Displays
(With DIC Buttons) on page 233andDIC
Operations and Displays (Without DIC Buttons)
on page 239.
URPA automatically turns back on each time
the vehicle is started.
How the System Works when Backing
If the shift lever is in REVERSE (R), URPA
detects objects close to the rear bumper. The
rst time an object is detected a single beep will
sound. If an object is detected at a REVERSE (R)
speed between 0 mph (0 km/h) and 5 mph
(8 km/h), the following describes what will occur
based on your distance to a detected object
located behind the vehicle:
At distances between 40 inches (1 m) and 8 ft
(2.5 m), a single amber light will come on.
At distances between 23 inches (0.6 m) and
40 inches (1 m), both amber lights will be on.
At distances between 12 inches (0.3 m) and
23 inches (0.6 m), all three lights (amber/
amber/red) will be on.
At distances less than 12 inches (0.3 m), a
beeping sound will repeat for a short time and
all three lights (amber/amber/red) will ash.
When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a
temporary condition, the message PARK ASSIST
OFF will display on the DIC screen and a red
light will come on the URPA display when the shift
lever is moved into REVERSE (R). This occurs
under the following conditions:
The parking brake pedal is depressed.
A trailer was attached to your vehicle, or a
bicycle or an object was hanging out of
your trunk during your last drive when you
turned off the vehicle. If the attached objects
are removed from your vehicle before the start
of your next drive, the system will return to
normal operation unless an object is detected
when the vehicle is shifted into REVERSE (R).
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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
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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.
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Dinghy Towing
If you have a front-wheel-drive vehicle, it can be
dinghy towed from the front. These vehicles
may also be towed by putting the front wheels on
a dolly. See “Dolly Towing” later in this section.
If you have an all-wheel-drive vehicle, it can
be dinghy towed from the front. You can also tow
these vehicles by placing them on a platform
trailer with all four wheels off of the ground.
These vehicles cannot be towed using a dolly.
For vehicles being dinghy towed, the vehicle
should be run at the beginning of each day and
at each RV fuel stop for about ve minutes.
This will ensure proper lubrication of transmission
components. Put the IGN (Ignition) fuse in to
start the vehicle.To tow your vehicle from the front with all four
wheels on the ground:
1. Position the vehicle to tow and then secure it.
2. Turn the ignition to OFF.
3. Set the parking brake.
4. To prevent your battery from draining while
the vehicle is being towed, remove the IGN
(Ignition) fuse from the underhood fuse block.
SeeUnderhood Fuse Block on page 493.
5. Turn the ignition to ACCESSORY.
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6. Shift your transmission to NEUTRAL (N).
7. Release the parking brake.
Notice:If you tow your vehicle without
performing each of the steps listed under
“Dinghy Towing,” you could damage the
automatic transmission. Be sure to follow all
steps of the dinghy towing procedure prior
to and after towing your vehicle.
Notice:If you exceed 65 mph (105 km/h) while
towing your vehicle, it could be damaged.
Never exceed 65 mph (105 km/h) while towing
your vehicle.
Once you have reached your destination, do the
following:
1. Set the parking brake.
2. Turn the ignition key to OFF and remove the
key from the ignition.
3. Reinstall the IGN (Ignition) fuse.
Notice:Don’t tow a vehicle with the front
drive wheels on the ground if one of the front
tires is a compact spare tire. Towing with
two different tire sizes on the front of the
vehicle can cause severe damage to the
transmission.Dolly Towing (All-Wheel-Drive Vehicles)
All-wheel-drive vehicles must not be towed with
two wheels on the ground. To properly tow
these vehicles, they should be placed on a
platform trailer with all four wheels off of the
ground or dinghy towed from the front.
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Dolly Towing (Front-Wheel-Drive
Vehicles Only)
To tow your front-wheel-drive vehicle from the
front with two wheels on the ground:
1.
Put the front wheels on a dolly.
2.Move the shift lever to PARK (P).
3.Set the parking brake and then remove the key.
4.Clamp the steering wheel in a straight-ahead
position with a clamping device designed
for towing.
5. Release the parking brake.
Towing Your Vehicle From the Rear
Notice:Towing your vehicle from the rear
could damage it. Also, repairs would not
be covered by the warranty. Never have your
vehicle towed from the rear.
Do not tow your vehicle from the rear.
370

Driving on Grades
Your vehicle is designed primarily as a passenger
and load carrying vehicle. If you tow a trailer,
your vehicle will require more frequent
maintenance due to the additional load. Because
of the added load of the trailer, your vehicle’s
engine may overheat on hot days, when going up
a long or steep grade with a trailer. If the engine
coolant temperature gage indicates overheating,
turn off the air conditioning to reduce engine load,
pull off the road and stop in a safe spot.
Reduce speed and shift to a lower gear before
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
On a long uphill grade, shift down and reduce
your speed to around 55 mph (88 km/h) to reduce
the possibility of the engine and the transmission
overheating.
Parking on Hills
{CAUTION:
You really should not park your vehicle,
with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured, and
both your vehicle and the trailer can be
damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift
into PARK (P).
When parking uphill, turn your wheels away
from the curb. When parking downhill,
turn your wheels into the curb.
2. Have someone place chocks behind the
trailer wheels.
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3. When the chocks are in place, release the
regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often
when you’re pulling a trailer. SeeScheduled
Maintenance on page 502for more information.
Things that are especially important in trailer
operation are automatic transmission uid
(don’t overll), engine oil, axle lubricant, drive
belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will
help you nd them quickly. If you’re trailering,
it’s a good idea to review this information before
you start your trip.
Check periodically to see that all hitch nuts and
bolts are tight.
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