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Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
DRIVING AND OPERATING 227
and fuel economy. If the octane is less
than 91, the engine could be damaged
and the repairs would not be covered
by the vehicle warranty. If heavy
knocking is heard when using gasoline
rated at 93 octane, the engine needs
service.
Prohibited Fuels
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
(Continued)
Caution (Continued)
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 0227.
Fuel Additives
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.
Filling the Tank
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
(Continued)
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Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
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DRIVING AND OPERATING 229
{Warning
If a fire starts while you are
refueling, do not remove the nozzle.
Shut off the flow of fuel by shutting
off the pump or by notifying the
station attendant. Leave the area
immediately.
Filling the Tank with a Portable
Gas Can
If the vehicle runs out of fuel and
must be filled from a portable gas can:
1. Locate the capless funnel adapter from under the carpet in
the trunk.
If this is a professional vehicle,
see the Coachbuilder’s Owner
Manual for funnel adapter
location. 2. Insert and latch the funnel into
the capless fuel system.
{Warning
Attempting to refuel without using
the funnel adapter may cause fuel
spillage and damage the capless
fuel system. This could cause a fire
and you or others could be badly
burned and the vehicle could be
damaged.
3. Remove and clean the funnel adapter and return to the storage
location.
Filling a Portable Fuel
Container
{Warning
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel vapor.
(Continued)
Warning (Continued)
You can be badly burned and the
vehicle damaged if this occurs. To
help avoid injury to you and others:
. Dispense fuel only into
approved containers.
. Do not fill a container while
it is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.
. Bring the fill nozzle in
contact with the inside of the
fill opening before operating
the nozzle. Contact should be
maintained until the filling is
complete.
. Do not smoke while
pumping fuel.
. Avoid using electronic
devices.
Page 354 of 376

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
ONSTAR 353
Press=to:
. Open the OnStar app on the
infotainment display. See the
infotainment manual for
information on how to use the
OnStar app.
Or
. Make a call, end a call, or answer
an incoming call.
. Give OnStar Hands-Free Calling
voice commands.
. Give OnStar Turn-by-Turn
Navigation voice commands.
. Obtain and customize the Wi-Fi
hotspot name or SSID and
password, if equipped. PressQto connect to an Advisor to:
. Verify account information or
update contact information.
. Get driving directions.
. Receive a Diagnostic check of the
vehicle's key operating systems.
. Receive Roadside Assistance.
. Manage Wi-Fi Settings,
if equipped.
Press
>to get a priority connection
to an OnStar Advisor available 24/7 to:
. Get help for an emergency.
. Be a Good Samaritan or respond
to an AMBER Alert.
. Get assistance in severe weather
or other crisis situations and find
evacuation routes.
OnStar Services
Emergency
Emergency Services require an active
safety and security plan. With
Automatic Crash Response, built-in
sensors can automatically alert a
specially trained OnStar Advisor who
is immediately connected in to the
vehicle to help.
Press
>for a priority connection to
an OnStar Advisor who can contact
emergency service providers, direct
them to your exact location, and relay
important information.
With OnStar Crisis Assist, specially
trained Advisors are available
24 hours a day, 7 days a week, to
provide a central point of contact,
assistance, and information during a
crisis.
With Roadside Assistance, Advisors
can locate a nearby service provider to
help with a flat tire, a battery jump,
or an empty gas tank.