brakes BUICK REGAL 2015 User Guide

Black plate (31,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-31
Drive Systems
All-Wheel Drive
If equipped, this feature transfers
torque to the rear wheels as
required. It is fully automatic, and
adjusts itself as needed for road
conditions.
All-Wheel Drive (AWD) performance
is automatically reduced when you
use the compact spare. To restore
full AWD performance, and prevent
excessive wear to the clutch in the
AWD system, replace the compact
spare tire with a full-size tire as
soon as possible. SeeCompact
Spare Tire on page 10-76.
Brakes
Antilock Brake
System (ABS)
This vehicle has ABS, an advanced
electronic braking system that helps
prevent a braking skid.
When 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. See Antilock
Brake System (ABS) Warning Light
on page 5-24. 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

Black plate (32,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-32 Driving and Operating
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
The Electric Parking Brake (EPB)
switch is on the center console. The
EPB can always be activated, even
if the ignition is off. To prevent
draining the battery, avoid repeated
cycles of the EPB when the engine
is not running.The system has a red parking brake
status light and an amber parking
brake warning light. See
Electric
Parking Brake Light on page 5-24
and Service Electric Parking Brake
Light on page 5-24. There are also
parking brake-related Driver
Information Center (DIC) messages.
See Brake System Messages on
page 5-39. In case of insufficient
electrical power, the EPB cannot be
applied or released.
Before leaving the vehicle, check
the red parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Lift up the EPB switch momentarily.

Black plate (34,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-34 Driving and Operating
Automatic EPB Release
The EPB will automatically release if
the vehicle is running, placed into
gear, and an attempt is made to
drive away. Avoid rapid acceleration
when the EPB is applied, to
preserve parking brake lining life.
The EPB can also be used to
prevent roll back for vehicles with a
manual transmission taking off on a
hill. When no roll back is desired, an
applied EPB will allow both feet to
be used for the clutch and
accelerator pedals in preparation for
starting the vehicle moving in the
intended direction. In this case,
there is no need to push the switch
to release the EPB.
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)
If equipped, Hill Start Assist (HSA)
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 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 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).

Black plate (35,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-35
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 vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See
If the Vehicle Is Stuck on
page 9-9 and“Turning the Systems
Off and On” later in this section.
The indicator light for both systems
is in the instrument cluster. This
light will:
.Flash when TCS is limiting
wheel spin.
.Flash when StabiliTrak is
activated.
.Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC), and
dcomes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.

Black plate (38,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-38 Driving and Operating
Cruise Control
With cruise control the vehicle can
maintain a speed of about 40 km/h
(25 mph) or more without keeping
your foot on the accelerator. Cruise
control does not work at speeds
below 40 km/h (25 mph).
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.If equipped with the Traction Control
System (TCS), the system may
begin to limit wheel spin while you
are using cruise control. If this
happens, the cruise control will
automatically disengage. See
Traction Control/Electronic Stability
Control on page 9-35. If a collision
alert occurs when cruise control is
activated, cruise control is
disengaged. See
Forward Collision
Alert (FCA) System on page 9-52.
When road conditions allow you to
safely use it again, the cruise
control can be turned back on.
If the brakes are applied, the cruise
control disengages.
5(On/Off): Press to turn cruise
control on or off. A white indicator
comes on in the instrument cluster
when cruise is turned on.
RES+ (Resume/Accelerate): If
there is a set speed in memory,
press the control up briefly to
resume to that speed or hold
upwards to accelerate. If cruise
control is already active, use to
increase vehicle speed.

Black plate (39,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-39
SET−(Set/Coast): Press the
control down briefly to set the speed
and activate cruise control. If cruise
control is already active, use to
decrease vehicle speed.
*(Cancel): Press to disengage
cruise control without erasing the
selected set speed.
Setting Cruise Control
If
5is on when not in use, SET− or
RES+ could get bumped and go into
cruise when not desired. Keep
5
off when cruise is not being used.
1. Press the
5button to turn the
cruise system on.
2. Get up to the speed desired.
3. Press and release the SET− control on the steering wheel.
The desired set speed briefly
appears in the instrument panel
cluster.
4. Remove foot from the accelerator. The cruise control indicator on the
instrument cluster turns green after
cruise control has been set to the
desired speed. See
Instrument
Cluster (Uplevel Cluster) on
page 5-12 orInstrument Cluster
(Base Level Cluster) on page 5-8.
Resuming a Set Speed
If the cruise control is set at a
desired speed and then the brakes
are applied or the
*is pressed, the
cruise control is disengaged without
erasing the set speed from memory.
Once the vehicle reaches about
40 km/h (25 mph) or more, press
RES+ up briefly. The vehicle returns
to the previous set speed.
Increasing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold RES+ up until
the desired speed is reached,
then release it.
.To increase vehicle speed in
small increments, press RES+
up briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) faster.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster
(Uplevel Cluster) on page 5-12 or
Instrument Cluster (Base Level
Cluster) on page 5-8. The increment
value used depends on the units
displayed.
Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold SET− down until
the desired lower speed is
reached, then release it.
.To slow down in small
increments, press SET− down
briefly. For each press, the
vehicle goes about 1.6 km/h
(1 mph) slower.

Black plate (41,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-41
conditions allow ACC to be safely
used, the ACC can be turned
back on.
ACC will not engage if the TCS or
electronic stability control system is
disabled.
{Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see“Alerting the Driver” in
this section. Complete attention is
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving on page 9-3.
{Warning
Adaptive Cruise Control will not
detect or brake for children,
pedestrians, animals, or other
objects.
Do not use Adaptive Cruise
Control when:
.On winding and hilly roads or
when the sensors are
blocked by snow, ice, or dirt.
The system may not detect a
vehicle ahead. Keep the
entire front of the vehicle
clean.
.Visibility is low, such as in
fog, rain, or snow conditions.
Adaptive Cruise Control
performance is limited under
these conditions.
.On slippery roads where fast
changes in tire traction can
cause excessive wheel slip.
](On/Off): Press to turn the
system on or off. The indicator turns
white on the instrument cluster
when ACC is turned on.
RES+ (Resume/Accelerate):
Press the control up briefly to make
the vehicle resume to a previously
set speed, or hold upwards to
accelerate. If cruise control is
already active, use to increase
vehicle speed.

Black plate (42,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-42 Driving and Operating
SET–(Set/Coast): Press the
control down briefly to set the speed
and activate ACC. If cruise control is
already active, use to decrease
vehicle speed.
*(Cancel): Press to disengage
ACC without erasing the selected
set speed.
3(Follow Distance Gap): Press
to select a following gap time (or
distance) setting for ACC of Far,
Medium, or Near.
Setting Adaptive Cruise Control
If the cruise button is on when not in
use, it could get pressed and go into
cruise when not desired. Keep the
cruise control button off when cruise
is not being used.
Select the set speed desired for
cruise. This is the vehicle speed
when no vehicle is detected in
its path.
ACC will not set at a speed less
than 25 km/h (16 mph), although it
can be resumed when driving at
lower speeds. To set ACC:
1. Press
].
2. Get up to the desired speed.
3. Press and release the SET– control on the steering wheel.
4. Remove foot from the accelerator.
After ACC is set, it may immediately
apply the brakes if a vehicle ahead
is detected closer than the selected
following gap.
The ACC indicator displays on the
instrument cluster. When ACC is
active, the indicator turns green.
Be mindful of speed limits,
surrounding traffic speeds, and
weather conditions when selecting
the set speed. Resuming a Set Speed
If the ACC is set at a desired speed
and then the brakes are applied,
ACC is disengaged without erasing
the set speed from memory.
To begin using ACC again, press
RES+ up briefly on the steering
wheel. The vehicle returns to the
previous set speed.
Increasing Speed While ACC is at
a Set Speed
If ACC is already activated, do one
of the following:
.Use the accelerator to get to the
higher speed. Press SET–
down.
Release the control and the
accelerator pedal. The vehicle
will now cruise at the higher
speed.
When the accelerator pedal is
pressed, ACC will not brake
because it is overridden.
A warning message will appear
on the Driver Information Center
(DIC). See Cruise Control
Messages on page 5-39.

Black plate (45,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
Driving and Operating 9-45
When braking is active, the brake
lights will come on. The automatic
braking may feel or sound different
than if the brakes were applied
manually. This is normal.
Stationary or Very Slow-Moving
Objects
{Warning
Adaptive Cruise Control (ACC)
may not detect and react to
stopped or slow-moving vehicles
ahead of you. For example, the
system may not brake for a
vehicle it has never detected
moving. This can occur in
stop-and-go traffic or when a
vehicle suddenly appears due to
a vehicle ahead changing lanes.
Your vehicle may not stop and
could cause a crash. Use caution
when using ACC. Your complete
attention is always required while
driving and you should be ready
to take action and apply the
brakes.ACC Automatically Disengages
ACC may automatically disengage
and the driver will need to manually
apply the brakes to slow the
vehicle when:
.The sensors are blocked.
.The traction control system
(TCS) or electronic stability
control system has activated or
been disabled.
.No traffic or other objects are
being detected.
.There is a fault in the system.
A message indicating that cruise is
disengaging will appear on the DIC
and the ACC active symbol will not
be displayed when ACC is no longer
active.
Notification to Resume ACC
ACC will maintain a follow gap
behind a detected vehicle and slow
your vehicle to a stop behind that
vehicle. If the stopped vehicle ahead has
driven away and ACC has not
resumed, the vehicle ahead symbol
will flash as a reminder to check
traffic ahead before proceeding. In
addition, three beeps will sound.
See
“Go Notifier” in“Collision/
Detection Systems” underVehicle
Personalization on page 5-47.
When the vehicle ahead drives
away, press RES+ or the
accelerator pedal to resume cruise
control. If stopped for more than
two minutes or if the driver door is
opened and the driver safety belt is
unbuckled, the ACC automatically
applies the electric parking brake to
hold the vehicle. The electric
parking brake status light will turn
on. See Parking Brake on
page 9-32. To resume ACC and
release the electric parking brake,
press the accelerator pedal.
A DIC warning message may
display indicating to shift to P (Park)
before exiting the vehicle. See
Vehicle Messages on page 5-38.

Black plate (46,1)Buick Regal Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7576024) - 2015 - CRC - 9/15/14
9-46 Driving and Operating
{Warning
If ACC has stopped the vehicle,
and if ACC is disengaged, turned
off, or canceled, the vehicle will
no longer be held at a stop. The
vehicle can move. When ACC is
holding the vehicle at a stop,
always be prepared to manually
apply the brakes.
{Warning
Leaving the vehicle without
placing it in P (Park) can be
dangerous. Do not leave the
vehicle while it is being held at a
stop by ACC. Always place the
vehicle in P (Park) and turn off
the ignition before leaving the
vehicle.ACC Override
If using the accelerator pedal while
ACC is active, a warning message
on the DIC will indicate that
automatic braking will not occur.
See
Vehicle Messages on
page 5-38. ACC will resume
operation when the accelerator
pedal is not being pressed.
{Warning
The ACC will not automatically
apply the brakes if your foot is
resting on the accelerator pedal.
You could crash into a vehicle
ahead of you.
Curves in the Road
{Warning
On curves, ACC may not detect a
vehicle ahead in your lane. You
could be startled if the vehicle (Continued)
Warning (Continued)
accelerates up to the set speed,
especially when following a
vehicle exiting or entering exit
ramps. You could lose control of
the vehicle or crash. Do not use
ACC while driving on an entrance
or exit ramp. Always be ready to
use the brakes if necessary.
{Warning
On curves, ACC may respond to
a vehicle in another lane, or may
not have time to react to a vehicle
in your lane. You could crash into
a vehicle ahead of you, or lose
control of your vehicle. Give extra
attention in curves and be ready
to use the brakes if necessary.
Select an appropriate speed while
driving in curves.