brake light GMC TERRAIN 2010 User Guide

8-28 Driving and Operating
Ignition Positions
The ignition switch has four different
positions.
Notice:Using a tool to force the
key to turn in the ignition could
cause damage to the switch or
break the key. Use the correct
key, make sure it is all the way in,
and turn it only with your hand.
If the key cannot be turned by
hand, see your dealer/retailer. To shift out of P (Park), turn the
ignition to ON/RUN and apply the
brake pedal.
A (LOCK/OFF):
This is the only
position from which the key can be
removed. This locks the steering
wheel, ignition and automatic
transmission.
On vehicles with an automatic
transmission, the shift lever must be
in P (Park) to turn the ignition switch
to the LOCK/OFF position.
The ignition switch can bind in the
LOCK/OFF position with the wheels
turned off center. If this happens,
move the steering wheel from right
to left while turning the key to ACC/
ACCESSORY. If this does not work,
then the vehicle needs service. B (ACC/ACCESSORY):
This
position provides power to some of
the electrical accessories. It unlocks
the steering wheel and ignition. The
transmission is also unlocked in this
position on automatic transmission
vehicles. To move the key from
ACC/ACCESSORY to LOCK/OFF,
push in the key and then turn it to
LOCK/OFF.
C (ON/RUN): The ignition switch
stays in this position when the
engine is running. This position can
be used to operate the electrical
accessories, including the
ventilation fan and 12 volt power
outlet, as well as to display some
warning and indicator lights.

Driving and Operating 8-39
Brakes
Antilock Brake
System (ABS)
This vehicle has the Antilock Brake
System (ABS), an advanced
electronic braking system that helps
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. SeeAntilock
Brake System (ABS) Warning Light
on page 4‑20. 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 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.
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. The ABS pump or motor
might be heard operating, and the
brake pedal might be felt to pulsate,
but this is normal.
Braking in Emergencies
ABS allows the driver to steer and
brake at the same time. In many
emergencies, steering can help
more than even the very best
braking.

8-40 Driving and Operating
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
on page 4‑19. Notice:
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 park 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.
If you are towing a trailer and are
parking on a hill, see Driving
Characteristics and Towing Tipson
page 8‑58.
Brake Assist
This vehicle has a brake assist
feature 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 pulsations 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.

Driving and Operating 8-41
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. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After 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 to
ensure that there is no rolling back.
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
System (TCS)
The vehicle has a Traction Control
System (TCS) that limits wheel spin.
On a front-wheel-drive vehicle, the
system operates if it senses that
one or both of the front wheels are
spinning or beginning to lose
traction. On an All-Wheel-Drive
(AWD) vehicle, the system will
operate if it senses that any of the
wheels are spinning or beginning to
lose traction. When this happens,
the system brakes the spinning
wheel(s) and/or reduces engine
power to limit wheel spin.
The system may be heard or felt
while it is working, but this is
normal.The TCS/StabiliTrak warning light
will flash to indicate that the traction
control system is active.
This warning light comes on if there
is a problem with TCS, and the
system will not limit wheel spin.
Adjust your driving accordingly.
TCS automatically comes on
whenever the vehicle is started.
To limit wheel spin, especially in
slippery road conditions, the system
should always be left on. But, TCS
can be turned off if needed.
Notice:Do not repeatedly brake
or accelerate heavily when TCS is
off. The vehicle's driveline could
be damaged.

8-42 Driving and Operating
The TCS off light comes on and
“Traction Control Off”is displayed
on the Driver Information Center
(DIC) to indicate that the traction
control system has been turned off.
See Ride Control System Messages
on page 4‑33.
On AWD vehicles, when TCS is
turned off, the system may still
make noise. This is normal and
necessary with AWD hardware.
It may be necessary to turn the
system off if the vehicle ever gets
stuck in sand, mud or snow and
rocking the vehicle is required. See
If the Vehicle is Stuck
on page 8‑22for more information. See also
Winter Drivingon page 8‑20for
information on using TCS when
driving in snowy or icy conditions.
Traction control can be turned off by
pressing and releasing the TCS/
StabiliTrak button, on the console,
until the TCS/StabiliTrak light comes
on the instrument panel and
“Traction Control Off” appears in the
DIC. Press the button again to turn
the system back on. For information
on turning StabiliTrak off and on,
see “StabiliTrak System” following in
this section.
Adding non‐GM accessories can
affect the vehicle's performance.
See Accessories and Modifications
on page 9‑3for more information.
StabiliTrak System
The vehicle has a vehicle stability
enhancement system called
StabiliTrak. It is an advanced
computer controlled system that
assists with directional control of the
vehicle in difficult driving conditions.
StabiliTrak activates when the
computer senses a difference
between the intended path and the
direction the vehicle is actually
traveling. StabiliTrak selectively
applies braking pressure at any one
of the vehicle's brakes to help steer
the vehicle in the intended direction.

Driving and Operating 8-43
When the stability control system
activates, the Traction Control
System (TCS)/StabiliTrak light will
flash on the instrument panel. This
also occurs when traction control is
activated. A noise may be heard or
vibration may be felt in the brake
pedal. This is normal. Continue to
steer the vehicle in the intended
direction.If there is a problem detected with
StabiliTrak, a
“Service StabiliTrak”
message will be displayed on the
Driver Information Center (DIC).
When this message is displayed
and the StabiliTrak light comes on,
the system is not operational.
Driving should be adjusted
accordingly. See Ride Control
System Messages
on page 4‑33.
StabiliTrak comes on automatically
whenever the vehicle is started. To
assist with directional control of the
vehicle, the system should always
be left on.
StabiliTrak can be turned off by
pressing and holding the TCS/
StabiliTrak button, on the console,
until the TCS Off and StabiliTrak Off
lights come on the instrument panel
and “StabiliTrak Off” appears in the
DIC. For information on turning TCS
off and on, see “Traction Control
System (TCS)” earlier in this
section.
If cruise control is being used when
StabiliTrak activates, the cruise
control will automatically disengage.
Press the cruise control button to
reengage when road conditions
allow. See Cruise Control
on
page 8‑44for more information.

8-46 Driving and Operating
Reducing Speed While Using
Cruise Control
If the cruise control system is
already engaged,
.Move the thumbwheel toward
SET/−and hold until the desired
lower speed is reached, then
release it.
.To slow down in very small
amounts, move the thumbwheel
toward SET/− briefly. Each time
this is done, the vehicle goes
about 1.6 km/h (1 mph) slower. Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle's speed. When
you take your foot off the pedal, the
vehicle slows down to the previously
set cruise control speed.
Using Cruise Control on Hills
How well the cruise control works
on hills depends upon the vehicle's
speed, load, and the steepness of
the hills. When going up steep hills,
you might have to step on the
accelerator pedal to maintain the
vehicle's speed. When going
downhill, you might have to brake or
shift to a lower gear to maintain the
vehicle's speed. When the brakes
are applied the cruise control
shuts off. Ending Cruise Control
There are three ways to disengage
the cruise control:
.Step lightly on the brake pedal
or clutch; when cruise control
disengages, the indicator light
will go off.
.Press\.
.Press5to turn the cruise
control system off completely.
The cruise control cannot be
resumed.
Erasing Speed Memory
The cruise control set speed
memory is erased when the cruise
control or the ignition is turned off.

Driving and Operating 8-49
System Settings
Each time the vehicle is started
URPA defaults to the On setting.
Use theVehicle Personalization
on
page 4‑36menu to
configure URPA.
The settings are:
.On: Turns URPA on
.Off: Turns URPA off
.Tow Bar: Use when a tow bar is
attached to the vehicle
Tow Bar
When the tow bar setting is used,
an area of 16 cm (6 in) around the
hitch is not detected by the system.
When the System Does Not
Seem to Work Properly
If the URPA system does not
activate due to a temporary
condition, the message Park Assist
Off displays on the DIC and a red
light is shown on the rear URPA
display when the shift lever is
moved into R (Reverse). This can
occur under the following
conditions:
.The ultrasonic sensors are not
clean. Keep the vehicle's rear
bumper free of mud, dirt, snow,
ice and slush. For cleaning
instructions, see Exterior Care
on page 9‑85.
.A trailer was attached to the
vehicle, or an object was
hanging out of the liftgate during
the last drive cycle, a red light
may come on in the rear display.
Once the attached object is
removed, URPA will return to
normal operation.
.A tow bar is attached to the
vehicle and the tow bar setting is
not being used, or an odd
shaped tow bar is attached to
the vehicle and the tow bar
setting is being used.
.The vehicle's bumper is
damaged. Take the vehicle to
your dealer/retailer to repair the
system.
.Other conditions may affect
system performance, such as
vibrations from a jackhammer or
the compression of air brakes on
a very large truck.
If the system is still disabled, after
driving forward at least 25 km/h
(15 mph), take the vehicle to your
dealer/retailer.

8-66 Driving and Operating
Trailer Sway
Control (TSC)
The vehicle has a Trailer Sway
Control (TSC) feature as part of the
StabiliTrak system. If TSC detects
that the trailer is swaying, the
vehicle's brakes are automatically
applied.
When TSC is applying the brakes,
the TCS/StabiliTrak indicator light
flashes to notify the driver to reduce
speed. SeeTraction Control System
(TCS)/StabiliTrak
®Lighton
page 4‑21. If the trailer continues to
sway, StabiliTrak will reduce engine
torque to help slow the vehicle.
TSC will not function if StabiliTrak is
turned off.
Conversions and
Add-Ons
Add-On Electrical
Equipment
Notice: Do not add anything
electrical to the vehicle unless
you check with your dealer/
retailer first. Some electrical
equipment can damage the
vehicle and the damage would
not be covered by the vehicle's
warranty. Some add-on electrical
equipment can keep other
components from working as
they should. Add-on equipment can drain the
vehicle battery, even if the vehicle is
not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicleon page 2‑38and
Adding
Equipment to the Airbag-Equipped
Vehicle on page 2‑38.

Vehicle Care 9-23
Brakes
This vehicle has disc brakes. Disc
brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
an accident. When the brake
wear warning sound is heard,
have the vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when the
brakes are first 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
specifications in
Capacities and
Specifications on page 11‑2.
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 designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes —for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.