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246 Driving and Operating
{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
not in proper condition; or if
the sun shines directly into
the camera.
. Detect road edges.
. Detect lanes on winding or
hilly roads.
(Continued)
Warning (Continued)
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 or on
roads with unclear lane markings,
such as construction zones.
{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
LKA uses a camera sensor installed
on the windshield ahead of the
rearview mirror to detect lane
markings. It may provide brief
steering assist if it detects an
unintended lane departure. It may
further provide an audible alert or
the driver seat may pulse indicating
that a lane marking has been
crossed.
To turn LKA on and off, press
A
on the center console. If equipped,
the indicator light on the button
comes on when LKA is on and turns
off when LKA is disabled.
When on,
Ais white, if equipped,
indicating that the system is not
ready to assist.
Ais green if LKA
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Driving and Operating 247
is ready to assist. LKA may assist
by gently turning the steering wheel
if the vehicle approaches a detected
lane marking.
Ais amber when
assisting. It may also provide a
Lane Departure Warning (LDW)
alert by flashing
Aamber if the
vehicle crosses a detected lane
marking. 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, an alert and chime may be
provided. Steer the vehicle to
dismiss. LKA may become
temporarily unavailable after
repeated take steering alerts.
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.
A system unavailable message may
display if the camera is blocked.
The LKA system does not need
service.
A camera blocked message may
display if the camera is blocked.
Some driver assistance systems
may have reduced performance or
not work at all. An LKA or LDW
unavailable message may display if
the systems are temporarily
unavailable. This message could be
due to a blocked camera. The LKA
system does not need service.
Clean the outside of the windshield
behind the rearview mirror. 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.
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248 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)
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87—
(R+M)/2 —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.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
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Recommended Fuel (LTG
- 2.0L L4 Turbo Engine)
Premium unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 93—
(R+M)/2 —is highly recommended
for best performance and fuel
economy. Unleaded gasoline with
an octane rated as low as 87 can be
used. 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. Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
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.
. Fuel with any amount of
methanol, methylal,
ferrocene, and aniline.
These fuels can corrode
metal fuel system parts or
damage plastic and rubber
parts.
(Continued)
Caution (Continued)
.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) 0249.
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250 Driving and Operating
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.
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
(Continued)
Caution (Continued)
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.
. Diesel-water emulsions,
such as Aquazole.
. Aftermarket diesel fuel
additives, which contain
alcohols, organo-metallic
additives, or water
emulsifiers.
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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.
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 of
conventional 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) 0256.
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,
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.
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252 Driving and Operating
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.
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) 0256.
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 0186.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.
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{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.
Caution
Water in the diesel fuel can
corrode internal components of
the fuel system and lead to
severe damage. It can also
support fungus or bacteria
growth, which can damage the
fuel system and Fuel Operated
Heater (FOH), if equipped. Even
with a diesel fuel biocide, the fuel
system may still need to be
cleaned. Your dealer can advise
of the appropriate solution.(Continued)
Caution (Continued)
If the fuel tank needs to be
purged to remove water, see your
dealer or a qualified technician.
Improper purging can damage the
fuel system and block the FOH.
As an added precaution, drain the
diesel fuel filter of residual water at
every engine oil change. If the
WATER IN FUEL - CONTACT
SERVICE message comes on
frequently, even after draining water
from the fuel filter, see your dealer. Water in Fuel Troubleshooting
If the WATER IN FUEL - CONTACT
SERVICE message comes on:
Problem Recommended
Action
Message
displays but
goes off during
the ignition
cycle. The fuel filter is
partially filled
with water. Drain
the water as
soon as
possible. See
"Removing
Water from the
Fuel Filter"
following.