2019 GMC TERRAIN 121

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 257
Left Side MirrorDisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror LCA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
the next lane over in that blind zone
or rapidly approaching that zone.
If the turn signal is activated in the
same direction as a detected
vehicle, this display will flash as an
extra warning not to change lanes.
LCA can be disabled through
vehicle personalization. See
“Collision/Detection Systems” under
Vehicle Personalization 0152.
If LCA is disabled by the driver, the
LCA mirror displays will not light up.
When the System Does Not
Seem to Work Properly
The LCA system requires some
driving for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight
highway road with traffic and
roadside objects (e.g., guardrails,
barriers).
LCA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. 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. LCA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle.
Attached objects may also interfere
with the detection of vehicles. This
is normal system operation; the
vehicle does not need service.
LCA may not always alert the driver
to vehicles in the next lane over,
especially in wet conditions or when driving on sharp curves. The system
does not need to be serviced. The
system may light up due to
guardrails, signs, trees, shrubs, and
other non-moving objects. This is
normal system operation; the
vehicle does not need service.
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" under
Exterior Care0367.
If the Driver Information Center
(DIC) displays the system
unavailable message after cleaning
both sides of the vehicle toward the
rear corners of the vehicle, see your
dealer.
If the LCA displays do not light up
when moving vehicles are in the
side blind zone or are rapidly
approaching this zone and the
system is clean, the system may
need service. Take the vehicle to
your dealer.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
258 Driving and Operating
Radio Frequency Information
SeeRadio Frequency Statement
0 405.
Lane Departure
Warning (LDW)
If equipped, LDW may help avoid
crashes due to unintentional lane
departures. It may provide a
warning if the vehicle is crossing a
detected lane marking without using
a turn signal in the lane departure
direction. Since this system is part
of the Lane Keep Assist (LKA)
system, read the entire LKA section
before using this feature.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid
crashes due to unintentional lane
departures. It may assist by gently
turning the steering wheel if the
vehicle approaches a detected lane
marking without using a turn signal
in that direction. It may also provide
a Lane Departure Warning (LDW)
system alert as the lane marking is
crossed. The LKA system will not assist or provide an LDW alert if it
detects that you are actively
steering. Override LKA by turning
the steering wheel. LKA uses a
camera to detect lane markings
between 60 km/h (37 mph) and
180 km/h (112 mph).
{Warning
The LKA system does not
continuously steer the vehicle.
It may not keep the vehicle in the
lane or give a Lane Departure
Warning (LDW) alert, even if a
lane marking is detected.
The LKA and LDW systems
may not:
. Provide an alert or enough
steering assist to avoid a
lane departure or crash.
. Detect lane markings under
poor weather or visibility
conditions. This can occur if
the windshield or
headlamps are blocked by
dirt, snow, or ice, if they are
(Continued)
Warning (Continued)
not in proper condition, or if
the sun shines directly into
the camera.
. Detect road edges.
. Detect lanes on winding or
hilly roads.
If LKA only detects lane markings
on one side of the road, it will
only assist or provide an LDW
alert when approaching the lane
on the side where it has detected
a lane marking. Even with LKA
and LDW, you must steer the
vehicle. Always keep your
attention on the road and
maintain proper vehicle position
within the lane, or vehicle
damage, injury, or death could
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LKA in
bad weather conditions.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 259
{Warning
Using LKA while towing a trailer
or on slippery roads could cause
loss of control of the vehicle and
a crash. Turn the system off.
How the System Works
The LKA camera sensor is on the
windshield ahead of the rearview
mirror.
To turn LKA on and off, press
A
on the center console.
When on,
Ais green if LKA is
available to assist and provide LDW
alerts. It may assist by gently
turning the steering wheel and
display
Aas amber if the vehicle
approaches a detected lane marking
without using a turn signal in that
direction. It may also provide an
LDW alert by flashing
Aamber
as the lane marking is crossed.
Additionally, there may be three
beeps, or the driver seat may pulse three times, on the right or left,
depending on the lane departure
direction.
Take Steering
The LKA system does not
continuously steer the vehicle.
If LKA does not detect active driver
steering, then an alert, chime,
or Driver Information Center (DIC)
message may be provided. Steer
the vehicle to dismiss.
When the System Does Not
Seem to Work Properly
The system performance may be
affected by:
.
Close vehicles ahead.
. Sudden lighting changes, such
as when driving through tunnels.
. Banked roads.
. Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help. A system unavailable message may
display if the camera is blocked.
The LKA system does not need
service.
LKA assistance and/or LDW alerts
may occur due to tar marks,
shadows, cracks in the road,
temporary or construction lane
markings, or other road
imperfections. This is normal system
operation; the vehicle does not need
service. Turn LKA off if these
conditions continue.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
260 Driving and Operating
Fuel
Top Tier Fuel (Gasoline)
GM recommends the use of TOP
TIER Detergent Gasoline to keep
the engine clean, reduce engine
deposits, and maintain optimal
vehicle performance. Look for the
TOP TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Top Tier Fuel (Diesel)
GM recommends the use of TOP
TIER Diesel Fuel to keep the engine
clean, reduce engine deposits, and
maintain optimal vehicle
performance. Look for the TOP
TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Diesel Fuel marketers and
applicable countries.
Recommended Fuel (LYX
- 1.5L L4 Turbo Engine)
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with a
posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Recommended Fuel (LTG
- 2.0L L4 Turbo Engine)
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 93 is
highly recommended for best
performance and fuel economy.
Unleaded gasoline with an octane
rated as low as 87 can be used.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 261
Using unleaded gasoline rated
below 93 octane, however, will lead
to reduced acceleration and fuel
economy. If knocking occurs, use a
gasoline rated at 93 octane as soon
as possible, otherwise, the engine
could be damaged. If heavy
knocking is heard when using
gasoline with a 93 octane rating, the
engine needs service.
Prohibited Fuels
(Gasoline)
Caution
Do not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:. For vehicles that are not
FlexFuel, fuel labeled
greater than 15% ethanol by
volume, such as mid-level
ethanol blends (16–50%
ethanol), E85, or FlexFuel.
(Continued)
Caution (Continued)
.Fuel with any amount of
methanol, methylal,
ferrocene, and aniline.
These fuels can corrode
metal fuel system parts or
damage plastic and rubber
parts.
. Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(MMT), which can damage
the emissions control
system and spark plugs.
. Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and performance,
and may decrease the life of
the emissions catalyst.
Fuels in Foreign
Countries
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see Prohibited
Fuels (Gasoline) 0261.
Fuel Additives (Gasoline)
TOP TIER Detergent Gasoline is
highly recommended for use with
your vehicle. If your country does
not have TOP TIER Detergent
Gasoline, add ACDelco Fuel
System Treatment Plus−Gasoline to
the vehicle’ s gasoline fuel tank at
every oil change or 15,000 km
(9,000 mi), whichever occurs first.
TOP TIER Detergent Gasoline and
ACDelco Fuel System Treatment
Plus−Gasoline will help keep your
vehicle’s engine fuel deposit free
and performing optimally.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
262 Driving and Operating
Fuel Additives (Diesel)
TOP TIER Detergent Diesel is
highly recommended for use with
your vehicle. If your area does not
have TOP TIER Detergent Diesel,
GM recommends the use of
ACDelco Diesel Fuel Conditioner.
This will help maintain optimal
engine performance. GM does not
recommend other aftermarket diesel
additives.
If low-quality diesel is used for
refueling, GM recommends adding
ACDelco Fuel System Treatment
Plus-Diesel to help clean engine
deposits. This is available only at
your GM dealer.
Fuel for Diesel Engines
The selection of a high-quality fuel
is important for maintaining optimum
vehicle performance. Diesel fuel
should meet or exceed the minimum
requirements in the most current
versions of the local fuel standards
Do not use fuel with more than 15
ppm sulfur.Do not use a diesel blend containing
more than 20% biodiesel by volume.
Caution
Use of fuel that does not comply
with the required technical
standards can lead to engine
power loss, increased wear,
or engine damage and may void
your warranty.
Some improper fuels are:
. Diesel fuel with the addition
of gasoline.
. Diesel fuel mixed with
engine oil or automatic
transmission fluid.
. Triglyceride fuels, such as
raw vegetable oil or animal
fat, in any form, including
with blends of diesel or
biodiesel.
. Marine diesel fuel and
fuel oils.
(Continued)
Caution (Continued)
.Diesel-water emulsions,
such as Aquazole.
. Aftermarket diesel fuel
additives, which contain
alcohols, organo-metallic
additives, or water
emulsifiers.
Caution
If the vehicle is accidentally
refueled with gasoline, do not
continue driving the vehicle.
Driving the vehicle will damage
the fuel system. Have the vehicle
towed to a qualified technician to
have the gasoline removed from
the tank and fuel system. Refuel
with Ultra Low Sulfur Diesel fuel.
It is also recommended to have
the fuel system flushed with Ultra
Low Sulfur Diesel, to ensure all
gasoline is removed.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 263
Some conditions, such as dirty fuel,
may decrease fuel filter life and a
CHANGE FUEL FILTER message
may come on in the Driver
Information Center (DIC).
Climate Grade Diesel Fuels
At temperatures below 0 °C (32 °F),
avoid using biodiesel blends above
5% by volume. Using such a fuel
may cause fuel filter plugging,
system gelling, and freezing, which
may adversely impact vehicle
starting.
Severe winter grade diesel fuel,
such as 1-D diesel fuel or Arctic
grade diesel fuel, can be used in
extreme cold temperatures (below
−18 °C or 0 °F); however, doing so
will reduce power and fuel economy.
Avoid using severe winter grade fuel
in warm or hot climates. It can result
in stalling, poor starting, and
damage to the fuel injection system.
Fuels improperly blended for cold
temperature operation may result in
restricted fuel filters. The vehicle is
equipped with a fuel heating system
to prevent gelling or waxing ofconventional diesel fuel and
biodiesel blends, but may not
prevent all cases.
In case of severe winter conditions,
the fuel filter may become clogged
by wax naturally present in the fuel.
To unclog it, move the vehicle to a
warm garage area and allow the
filter to warm up. The fuel filter may
need to be replaced. See
Fuel Filter
Replacement (Diesel) 0268.
Biodiesel
Biodiesel is a renewable fuel
produced from vegetable oils or
animal fats that have been
chemically modified to make it
compatible with diesel fuel.
Caution
Do not use home-made biodiesel
or home test kits because the
quality cannot be verified by
approved scientific methods. Do
not use raw vegetable oil or other
unmodified bio-oils, fats,
(Continued)
Caution (Continued)
or blends of vegetable oil with
diesel. They could damage the
fuel system and engine, and
damages would not be covered
by the vehicle warranty.
Biodiesel Blends
Fuels with a biodiesel content up to
20% by volume may be used (e.g.,
named B20). Only use biodiesel
blends up to 20% by volume that
comply with your country’ s or
region’s fuel standards.
Caution
Do not use blends containing
more than 20% biodiesel. Any
engine, fuel system, or exhaust
after-treatment system damage
would not be covered by the
vehicle warranty.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
264 Driving and Operating
As a renewable fuel, biodiesel
provides some environmental
benefits. However, biodiesel has
unique properties and needs to be
handled differently than diesel fuel.
Its use presents additional risks and
may not be appropriate in all
situations. Certain vehicle operating
modes increase these risks and
should be avoided.
Biodiesel fuel quality degrades with
time and exposure to high
temperature quicker than Ultra Low
Sulfur Diesel fuel. More frequent
refueling provides the best
opportunity to have a supply of fresh
fuel. Storage at hot ambient
temperatures will accelerate
biodiesel degradation.
If the vehicle is not driven often and
uses little fuel, or if it is stored for
extended periods of time, avoid the
use of biodiesel blended fuels
above 5% by volume. When the
vehicle is stored for longer than one
month, it should be run out of
biodiesel to below one-quarter tank,refueled with biodiesel-free fuel, and
driven several kilometers (miles)
before storage.
Cold Weather Operation
(Diesel)
In cold weather, the fuel filter may
become clogged by wax naturally
present in the fuel. To unclog it,
move the vehicle to a warm garage
area and allow the filter to warm up.
The fuel filter may need to be
replaced. See
Fuel Filter
Replacement (Diesel) 0268.
At temperatures below 0 °C (32 °F),
it is recommended to avoid using
biodiesel blends above 5% blend.
This blend may cause fuel filter
plugging, system gelling, and
freezing that may affect vehicle
starting. You may need to turn the
ignition on and off a few times
before the vehicle will start. Also,
idle the vehicle for a couple of
minutes before accelerating.
It is recommended to use Ultra Low
Sulfur No. 1-D diesel fuel or a blend
of No. 1-D and No. 2-D diesel fuel to enhance vehicle operation in cold
weather at temperatures below 0 °C
(32 °F). Use of No. 1-D diesel fuel
may lower the fuel economy. For
additional information for better cold
weather operation, see
Engine
Heater 0200.
Water in Fuel (Diesel)
Improper fuel tank inspection or
cleaning, or contaminated fuel from
suppliers, can cause water to be
pumped into the fuel tank along with
the diesel fuel. If a WATER IN FUEL
- CONTACT SERVICE message
displays, the water must be drained
immediately.
{Warning
Diesel fuel containing water is still
combustible. You or others could
be burned. If the fuel needs to be
drained, keep sparks, flames, and
smoking materials away from the
mixture.