2017 GMC ACADIA LIMITED parking brake

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
Driving and Operating 183
If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses 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
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake
To set the parking brake, hold the
regular brake pedal down, then
push the parking brake pedal down.
If the ignition is on, the brake
system warning light will come on.
SeeBrake System Warning
Light 0111.
Caution
Driving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, the brake
system warning light will be on and
a chime will sound warning you that
the parking brake is still on.

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
184 Driving and Operating
If you are towing a trailer and are
parking on a hill, seeDriving
Characteristics and Towing
Tips 0200.
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates. The
Brake Assist feature will
automatically disengage when the brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
This vehicle has a Hill Start Assist
(HSA) feature, which may be useful
when the vehicle is stopped on a
grade sufficient enough to activate
HSA. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After the driver
completely stops and holds the
vehicle in a complete standstill on a
grade, HSA will be automatically
activated. During the transition
period between when the driver
releases the brake pedal and starts
to accelerate to drive off on a grade,
HSA holds the braking pressure for
a maximum of two seconds to
ensure that there is no rolling. The
brakes will automatically release
when the accelerator pedal is
applied within the two-second
window. It will not activate if the
vehicle is in a drive gear and facing
downhill, or if the vehicle is facing
uphill and in R (Reverse).
Ride Control Systems
Traction Control/
Electronic Stability
Control
System Operation
The vehicle has a Traction Control
System (TCS) and StabiliTrak®, an
electronic stability control system.
These systems help limit wheel slip
and assist the driver in maintaining
control, especially on slippery road
conditions.
TCS activates if it senses that any
of the drive wheels are spinning or
beginning to lose traction. When this
happens, TCS applies the brakes to
the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak activates when the
vehicle senses a difference between
the intended path and the direction
the vehicle is actually traveling.
StabiliTrak selectively applies
braking pressure to any one of the

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
Driving and Operating 191
{Warning
The parking assist system does
not detect children, pedestrians,
bicyclists, animals, or objects
below the bumper or that are too
close or too far from the vehicle.
It is not available at speeds
greater than 8 km/h (5 mph). To
prevent injury, death, or vehicle
damage, even with parking assist,
always check the area around the
vehicle and check all mirrors
before backing.
How the System Works
RPA comes on automatically when
the shift lever is moved into
R (Reverse). A single beep sounds
to indicate the system is working.
An obstacle is indicated by audible
beeps. The interval between the
beeps becomes shorter as the
vehicle gets closer to the obstacle.
When the distance is less than
30 cm (12 in) the beeping is
continuous for five seconds.
Turning the System On and Off
The system can be disabled through
the Driver Information Center (DIC).
See“Park Assist” underDriver
Information Center (DIC) 0116.
Turn off RPA when towing a trailer.
RPA defaults to the on setting each
time the vehicle is started.
When the System Does Not
Seem to Work Properly
The following messages may be
displayed on the DIC:
SERVICE PARK ASSIST : If this
message occurs, take the vehicle to
your dealer to repair the system.
PARK ASST BLOCKED SEE
OWNERS MANUAL : This
message can occur under the
following conditions:
. The sensors are not clean. Keep
the vehicle's rear bumper free of
mud, dirt, snow, ice, and slush.
For cleaning instructions, see
Exterior Care 0278. .
The sensors are covered by
frost or ice. Frost or ice can form
around and behind the sensors
and may not always be seen;
this can occur after washing the
vehicle in cold weather. The
message may not clear until the
frost or ice has melted.
. A trailer was attached to the
vehicle, or an object was
hanging out of the liftgate during
the last drive cycle. Once the
object is removed, RPA will
return to normal operation.
. A tow bar is attached to the
vehicle.
. The bumper is damaged. Take
the vehicle to your dealer to
repair the system.
. Other conditions, such as
vibrations from a jackhammer or
the compression of air brakes on
a very large truck, are affecting
system performance.

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
202 Driving and Operating
When turning with a trailer, make
wider turns than normal so the
trailer will not strike soft shoulders,
curbs, road signs, trees or other
objects. Use the turn signal well in
advance and avoid jerky or sudden
maneuvers.
Turn Signals When Towing a
Trailer
The turn signal indicators on the
instrument cluster flash whenever
signaling a turn or lane change.
Properly hooked up, the trailer
lamps also flash, telling other
drivers the vehicle is turning,
changing lanes or stopping.
When towing a trailer, the arrows on
the instrument cluster flash for turns
even if the bulbs on the trailer are
burned out. Check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, thebrakes might have to be used so
much that they would get hot and no
longer work well.
The vehicle can tow in D (Drive).
Use a lower gear if the transmission
shifts too often.
The Tow/Haul Mode may be used if
the transmission shifts too often.
See
Tow/Haul Mode 0181.
When towing at high altitude on
steep uphill grades, engine coolant
boils at a lower temperature than at
normal altitudes. If the engine is
turned off immediately after towing
at high altitude on steep uphill
grades, the vehicle could show
signs similar to engine overheating.
To avoid this, let the engine run
while parked, preferably on level
ground, with the transmission in
P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating 0222.
Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the brake pedal
until the chocks absorb
the load.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
Driving and Operating 203
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedalwhile you:
.Start the engine.
. Shift into a gear.
. 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
The vehicle needs service more
often when pulling a trailer. See the
Maintenance Schedule 0289.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. Inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine
Overheating 0222.
Trailer Towing
Three important considerations
have to do with weight:
.
The weight of the trailer.
. The weight of the trailer tongue.
. The total weight on the vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
Speed, altitude, road grades,
outside temperature, special
equipment, and the amount of
tongue weight the vehicle can carry
must be considered. See “Weight of
the Trailer Tongue” later in this
section for more information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the required trailering equipment. The
weight of additional optional
equipment, passengers and cargo in
the tow vehicle must be subtracted
from the maximum trailer weight.
Use the following chart to determine
how much the vehicle can weigh,
based upon the vehicle model and
options.

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/31/16
206 Driving and Operating
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Always leave just enough slack so
the rig can turn. Never allow safety
chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 450 kg (1,000 lb) needs to have
its own brake system that is
adequate for the weight of the
trailer. Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted, and
maintained properly.
Because the vehicle has antilock
brakes, do not try to tap into the
vehicle's hydraulic brake system.
If you do, both brake systems will
not work well, or at all.
Trailer Wiring Harness
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.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
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 or a qualified service center.
If the back-up lamp circuit is not
functional, contact your dealer.
To help charge a remote
(non-vehicle) battery, press the Tow/
Haul Mode button at the end of the
shift lever. If the trailer is too light for
Tow/Haul Mode, turn on the
headlamps to help charge the
battery.
Electric Trailer Brake Control
Wiring Provisions
These wiring provisions for an
electric trailer brake controller are
included with the vehicle as part of
the trailer wiring package. The
instrument panel contains blunt cut
wires above the parking brake
assembly for the electric trailer
brake controller. The harness
contains the following wires:
.
Red/Black: Power Supply
. White: Brake Switch Signal

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/30/16
228 Vehicle Care
Infrequent Usage: Remove the
black, negative (−) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative (−) cable from the
battery or use a battery trickle
charger.
All-Wheel Drive
Transfer case fluid does not require
checking unless there is a fluid leak
or unusual noise. If required, have
the transfer case serviced by your
dealer.
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Apply both the parking brake and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.

GMC Acadia Limited Owner Manual (GMNA-Localizing-U.S.-10283134) -
2017 - crc - 3/30/16
Vehicle Care 229
Ignition Transmission
Lock Check
While parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
. The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to (Continued)
Warning (Continued)
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
. To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Front Wiper Blade
Windshield wiper blades should be
inspected for wear or cracking. See
Maintenance Schedule 0289.
Replacement blades come in
different types and are removed in
different ways. For the proper type
and size, see Maintenance
Replacement Parts 0299.
To replace the wiper blade
assembly: 1. Pull the windshield wiper assembly away from the
windshield.
2. Squeeze the tabs on each side
of the wiper blade assembly
and slide the assembly off the
end of the wiper arm.