
Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
228 Driving and Operating
{Warning
RAB may not avoid many types of
backing crashes. Do not wait for the
automatic braking to apply. This system
is not designed to replace driver braking
and only works in R (Reverse) when an
object is detected directly behind the
vehicle. It may not brake or stop in time
to avoid a crash. It will not brake for
objects when the vehicle is moving at
very low speeds. It does not detect
children, pedestrians, bicyclists, animals,
or objects below the bumper or that are
too close or too far from the vehicle. To
prevent injury, death, or vehicle damage,
even with RAB, always check the area
around the vehicle before and while
backing.
Pressing the brake pedal after the vehicle
comes to a stop will release RAB. If the
brake pedal is not pressed soon after the
stop, the Electric Parking Brake (EPB) may be
set. When it is safe, press the accelerator
pedal firmly at any time to override RAB.
{Warning
There may be instances where
unexpected or undesired automatic
braking occurs. If this happens, either
press the brake pedal or firmly press the
accelerator pedal to release the brakes
from the RAB system. Before releasing
the brakes, check the RVC and check the
area around the vehicle to make sure it is
safe to proceed.
Rear Cross Traffic Alert (RCTA)
If equipped, RCTA displays a red warning
triangle with a left or right pointing arrow
on the infotainment display to warn of
traffic coming from the left or right. This
system detects objects coming from up to
20 m (65 ft) from the left or right side of
the vehicle. When an object is detected,
either three beeps sound from the left or
right or three Safety Alert Seat pulses occur
on the left or right side, depending on the
direction of the detected vehicle.
Use caution while backing up when towing
a trailer, as the RCTA detection zones that
extend out from the back of the vehicle do
not move further back when a trailer is
towed.
Enhanced Automatic Parking Assist (APA)
If equipped, under certain conditions
Enhanced Automatic Parking Assist (APA) can
use sensors based on sonar technology
along the vehicle’s front, rear and sides to
detect a parking spot and automatically park
the vehicle. The vehicle will automatically
maneuver into a detected spot moving at or
near idle speed. It does this by
automatically steering, braking, accelerating,
and gear shifting. The driver must always be
prepared to apply braking if necessary. A
display and beeps help to guide the parking
maneuvers.
{Warning
APA may not always detect objects in the
parking space, objects that are not rigid
(e.g. shrubs and chain-link fences), objects
below the bumper, objects high off the
ground (e.g. flatbed trucks), hanging
objects, objects below ground level such
(e.g. large potholes), or moving objects
(e.g. pedestrians, cyclists, vehicles).
Always verify that the parking space is
appropriate for parking a vehicle. APA
may not respond to changes in the (Continued)

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 229
Warning (Continued)
parking space, such as movement of an
adjacent vehicle, or a person or object
entering the parking space. APA does not
detect or avoid traffic that is behind or
alongside of the vehicle. Always be
prepared to stop the vehicle during the
parking maneuver.
How to Activate Automatic Parking
To activate APA, press the soft-touch
button or hard switch
Ofor the system to
begin searching for a parking space while
driving forward at no greater than
30 km/h (18 mph). By default, APA searches
for parallel parking spaces to the right of
the vehicle up to the sensors’ range of 1.5 m
(5 ft). To search for a parking space to the
left, turn on the left turn signal or,
if available, change the side selection in the
infotainment display. To switch the parking
mode between parallel and perpendicular
press and hold
Owhile searching for a
valid parking spot or, if available, change the
parking mode in the infotainment display.
APA cannot park in all empty parking spots.
The parking spot must:
.Be sufficiently large to fit the vehicle
comfortably.
.Have an adjacent vehicle, wall, or pillar
for the system to align to.
After completely passing an eligible parking
spot, a beep sounds and a red stop symbol
is displayed in the driver information center.
Generally, APA selects the nearest empty
parking spot behind the vehicle, but under
some conditions may select a space that is
further back. Slow down and bring the
vehicle to a complete stop to begin.
Follow the displayed instructions. When
instructed to drive in reverse, shift to
R (Reverse) while holding the brakes. The
steering wheel will vibrate briefly as a
reminder to remove hands from the steering
wheel. Release the brakes slowly when the
vibration stops to begin automatic parking.
As the vehicle automatically steers, brakes, accelerates, and shifts gears into the parking
spot, check surroundings. Be prepared to
stop to avoid vehicles, pedestrians,
or objects.
A progress arrow displays the status of the
parking maneuver. Once automatic parking
is finished and the vehicle has come to a full
stop, FINAL POSITION - PRESS BRAKES
message will be displayed. Press and hold
the brakes, and APA will beep and display a
PARKING COMPLETE message. Shift the
vehicle to P (Park) and apply the parking
brake.
How to Activate Automatic Parallel Spot
Unparking Assist
To activate parallel spot unparking assist,
press the soft-touch button or hard switch
Oafter turning on the vehicle while
leaving it in P (Park) and the parking brake

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
244 Driving and Operating
When towing a trailer:
.Become familiar with and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. Even if not
required, you should install extended side
view mirrors if your visibility is limited or
restricted while towing.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.It is recommended to perform the first oil
change before heavy towing.
.During the first 800 km (500 mi) of trailer
towing, do not drive over 80 km/h
(50 mph) and do not make starts at full
throttle.
.Vehicles can tow in D (Drive). If the
transmission downshifts too often, a
lower gear may be selected using Manual
Mode SeeManual Mode 0206.
If equipped, the following driver assistance
features should be turned off when towing
a trailer:
.Adaptive Cruise Control (ACC)
.Super Cruise Control
.Lane Keep Assist (LKA)
.Park Assist
.Automatic Parking Assist (APA)
.Reverse Automatic Braking (RAB)
If equipped, the following driver assistance
features should be turned to alert or off
when towing a trailer:
.Automatic Emergency Braking (AEB)
.Intelligent Brake Assist (IBA)
.Front Pedestrian Braking (FPB)
If equipped with Lane Change Alert (LCA),
the LCA detection zones that extend back
from the side of the vehicle do not move
further back when a trailer is towed. Use
caution while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic Alert
(RCTA), use caution while backing up when
towing a trailer, as the RCTA detection zones
that extend out from the back of the vehicle
do not move further back when a trailer is
towed.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See “Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0203.
Towing a trailer requires experience. The
combination of the vehicle and trailer is
longer and not as responsive as the vehicle
itself. Get used to the handling and braking
of the combination by driving on a level
road surface before driving on public roads.
The trailer structure, the tires, and the
brakes must be all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.
Before driving, inspect all trailer hitch parts

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 245
and attachments, safety chains, electrical
connectors, lamps, tires, and mirrors. See
Towing Equipment0249. If the trailer has
electric brakes, start the combination
moving and then manually apply the trailer
brake controller to check that the trailer
brakes work. During the trip, occasionally
check that the cargo and trailer are secure
and that the lamps and any trailer brakes
are working.
Towing with a Stability Control System
When towing, the stability control system
might be heard. The system reacts to
vehicle movement caused by the trailer,
which mainly occurs during cornering. This is
normal when towing heavier trailers.
Following Distance
Stay at least twice as far behind the vehicle
ahead as you would when driving without a
trailer. This can help to avoid heavy braking
and sudden turns.
Passing
More passing distance is needed when
towing a trailer. The combination of the
vehicle and trailer will not accelerate as
quickly and is much longer than the vehicle
alone. It is necessary to go much farther beyond the passed vehicle before returning
to the lane. Pass on level roadways. Avoid
passing on hills if possible.
Backing Up
Hold the bottom of the steering wheel with
one hand. To move the trailer to the left,
move that hand to the left. To move the
trailer to the right, move that hand to the
right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Caution
Turn more slowly and make wider arcs
when towing a trailer to prevent damage
to your vehicle. Making very sharp turns
could cause the trailer to contact the
vehicle.
Make wider turns than normal when towing,
so the trailer will not go over soft shoulders,
over curbs, or strike road signs, trees,
or other objects. Always signal turns well in
advance. Do not steer or brake suddenly.
Driving on Grades
Reduce speed and shift to a lower gear
before starting down a long or steep
downhill grade. If the transmission is not
shifted down, the brakes may overheat and
result in reduced braking efficiency.
The vehicle can tow in D (Drive). Shift the
transmission to a lower gear if the
transmission shifts too often under heavy
loads and/or hilly conditions.
When towing at higher altitudes, engine
coolant will boil at a lower temperature
than at lower 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, 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 0265.

Buick E2UB-N Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14583509) - 2021 - CRC - 1/8/21
246 Driving and Operating
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer on a
level surface when possible.
When parking your vehicle and your trailer
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, gradually release the brake pedal to
allow the chocks to absorb the load of
the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.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
used to tow trailers. See Maintenance
Schedule 0314. It is especially important to
check the automatic transmission fluid,
engine oil, axle lubricant, belts, cooling
system, and brake system before and during
each trip.
Check periodically that all nuts and bolts on
the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0265.
Trailer Towing
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
(Continued)
Caution (Continued)
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity for
your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades, outside
temperature, dimensions of the front of the
trailer, and how frequently the vehicle is
used to tow a trailer.
When towing a trailer, the combined weight
of the vehicle, vehicle contents, trailer, and
trailer contents must be below all of the
maximum weight ratings for the vehicle,
including:
.GCWR: Gross Combined Weight Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight Rating