check engine CADILLAC XT6 2020 Owner's Guide

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
256 DRIVING AND OPERATING
{Warning
Trailer sway can result in a crash
and in serious injury or death, even
if the vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing
your foot from the accelerator. Then
pull over to check the trailer and
vehicle to help correct possible
causes, including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. SeeTowing Equipment
0 252 for trailer ratings and hitch
setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are designed
with stiff sidewalls to help prevent
sway and to support heavy loads.
These features can make it difficult to determine if the trailer tire pressures
are low only based on a visual
inspection.
Always check all trailer tire pressures
before each trip when the tires are
cool. Low trailer tire pressure is a
leading cause of trailer tire blowouts.
Trailer tires deteriorate over time. The
trailer tire sidewall will show the week
and year the tire was manufactured.
Many trailer tire manufacturers
recommend replacing tires more than
six years old.
Overloading is another leading cause
of trailer tire blowouts. Never load the
trailer with more weight than the tires
are designed to support. The load
rating is on the trailer tire sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default trailer
tire speed rating is 105 km/h (65 mph).
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See
Malfunction Indicator
Lamp (Check Engine Light) 0120.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle systems.
This could affect vehicle operation
and cause a crash. Such devices
may also access information stored
in the vehicle’s systems.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
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258 VEHICLE CARE
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 259
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 259
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 260
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 260
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 260
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 263
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 264
Engine Oil Life System . . . . . . . . . . . 266
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Engine Air Filter Life System . . . . 267
Engine Air Cleaner/Filter . . . . . . . . . 268
Cooling System . . . . . . . . . . . . . . . . . . . 269
Engine Overheating . . . . . . . . . . . . . . 272
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 273
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 275
Battery - North America . . . . . . . . . 276
Starter Switch Check . . . . . . . . . . . . . 276
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 277
Wiper Blade Replacement . . . . . . . 277
Windshield Replacement . . . . . . . . 278
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 279
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . . . . . 280
Bulb Replacement
LED Lighting . . . . . . . . . . . . . . . . . . . . . 280
Electrical System
Electrical System Overload . . . . . . 281
Fuses and Circuit Breakers . . . . . . 281
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Instrument Panel Fuse Block . . . . 285
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
All-Season Tires . . . . . . . . . . . . . . . . . . 290
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 290
Summer Tires . . . . . . . . . . . . . . . . . . . . 291 Tire Sidewall Labeling . . . . . . . . . . . 291
Tire Designations . . . . . . . . . . . . . . . . . 293
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 294
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 296
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . . . . . . 298
Tire Pressure Monitor System . . . 298
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 299
Tire Inspection . . . . . . . . . . . . . . . . . . . 303
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 303
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 304
Buying New Tires . . . . . . . . . . . . . . . . 305
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Uniform Tire Quality Grading . . . 307
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Wheel Replacement . . . . . . . . . . . . . . 308
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 309
If a Tire Goes Flat . . . . . . . . . . . . . . . . 310
Tire Changing . . . . . . . . . . . . . . . . . . . . . 311
Compact Spare Tire . . . . . . . . . . . . . . 317

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
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264 VEHICLE CARE
1.Engine Air Cleaner/Filter 0268.
2. Engine Oil Fill Cap. See Engine Oil
0 264.
3. Engine Oil Dipstick. See Engine
Oil 0264.
4. Engine Cooling Fan (Out of View). See Cooling System 0269.
5. Brake Fluid Reservoir. See Brake
Fluid 0275.
6. Battery - North America 0276.
7. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 269.
8. Positive (+) Battery Terminal (Under Cover). See Jump Starting
- North America 0318.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 273.
10. Engine Compartment Fuse Block
0282.
11. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0318.Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
. Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” in this
section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0266.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick handle is a loop. See
Engine
Compartment Overview 0263 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy
improves when checking a cold
engine prior to starting. Remove
the dipstick and check the level.

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VEHICLE CARE 265
.If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is warm,
or at least 30 minutes if the
engine is not warm. Pull out the
dipstick, wipe it with a clean paper
towel or cloth, then push it back
in all the way. Remove it again,
keeping the tip down, and check
the level.
When to Add Engine Oil
If the oil is below the cross-hatched
area at the tip of the dipstick and the
engine has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See “Selecting the Right
Engine Oil” later in this section for an
explanation of what kind of oil to use.
For engine oil crankcase capacity, see
Capacities and Specifications 0347.
Caution
Do not add too much oil. Oil levels
above or below the acceptable
operating range shown on the
dipstick are harmful to the engine.
If the oil level is above the
operating range (i.e., the engine has
so much oil that the oil level gets
above the cross-hatched area that
shows the proper operating range),
the engine could be damaged. Drain
the excess oil or limit driving of the
vehicle, and seek a service
professional to remove the
excess oil.
See Engine Compartment Overview
0 263 for the location of the engine oil
fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when finished.
Selecting the Right Engine Oil
Selecting the right engine oil depends
on both the proper oil specification
and viscosity grade. See Recommended
Fluids and Lubricants 0343.
Specification
Use full synthetic engine oils that
meet the dexos1 specification. Engine
oils that have been approved by GM
as meeting the dexos1 specification
are marked with the dexos1 approved
logo. See www.gmdexos.com.
Caution
Failure to use the recommended
engine oil or equivalent can result
in engine damage not covered by
the vehicle warranty.

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Viscosity Grade
Use SAE 5W-30 viscosity grade
engine oil.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below−29 °C
(−20 °F), an SAE 0W-30 oil may be
used. An oil of this viscosity grade will
provide easier cold starting for the
engine at extremely low temperatures.
When selecting an oil of the
appropriate viscosity grade, it is
recommended to select an oil of the
correct specification. See
“Specification ”earlier in this section.
Engine Oil Additives/Engine Oil
Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for
good performance and engine
protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain
elements that can be unhealthy for
your skin and could even cause
cancer. Do not let used oil stay on
your skin for very long. Clean your
skin and nails with soap and water,
or a good hand cleaner. Wash or
properly dispose of clothing or rags
containing used engine oil. See the
manufacturer's warnings about the
use and disposal of oil products.
Used oil can be a threat to the
environment. If you change your own
oil, be sure to drain all the oil from
the filter before disposal. Never
dispose of oil by putting it in the trash
or pouring it on the ground, into
sewers, or into streams or bodies of
water. Recycle it by taking it to a place
that collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system
that indicates when to change the
engine oil and filter. This is based on a
combination of factors which include engine revolutions, engine
temperature, and miles driven. Based
on driving conditions, the mileage at
which an oil change is indicated can
vary considerably. For the oil life
system to work properly, the system
must be reset every time the oil is
changed.
When the system has calculated that
oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the
oil as soon as possible within the next
1 000 km (600 mi). It is possible that,
if driving under the best conditions,
the oil life system might indicate that
an oil change is not necessary for up
to a year. The engine oil and filter
must be changed at least once a year
and at this time the system must be
reset. Your dealer has trained service
people who will perform this work and
reset the system. It is also important
to check the oil regularly over the
course of an oil drain interval and
keep it at the proper level.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
268 VEHICLE CARE
to change an engine air filter depends
on driving and environmental
conditions.
When to Change the Engine Air
Filter
When the Driver Information Center
(DIC) displays a message to replace
the engine air filter at the next oil
change, follow this timing.
When the DIC displays a message to
replace the engine air filter soon,
replace the engine air filter at the
earliest convenience.
The system must be reset after the
engine air filter is changed.
If the DIC displays a message to check
the engine air filter system, see your
dealer.
How to Reset the Engine Air
Filter Life System
To reset:1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information Center
(DIC) 0128. 3. Press
Ton the steering wheel to
move to the Reset/Disable
display area. Select Reset then
press the thumbwheel for several
seconds.
4. Press the thumbwheel to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the passenger
side of the vehicle. See Engine
Compartment Overview 0263.
When to Inspect/Replace the
Engine Air Cleaner/Filter
If the vehicle is not equipped with the
engine air filter life system, see
Maintenance Schedule 0333.
How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/filter,
make sure that the engine air cleaner/
filter housing and nearby components are free of dirt and debris. Remove the
engine air cleaner/filter. Do not clean
the engine air cleaner/filter or
components with water or
compressed air.
To inspect or replace the engine air
cleaner/filter:
1. Remove the five screws on top of
the engine air cleaner/filter
housing.
2. Lift the air cleaner/filter cover housing away from the engine.
3. Pull out the filter.
4. Inspect or replace the engine air cleaner/filter.

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5. Reverse Steps 1–3 to reinstall thefilter cover housing.
6. If equipped, reset the engine air filter life system after replacing
the engine air filter. See Engine
Air Filter Life System 0267.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. Use caution
when working on the engine. Do
not start the engine or drive the
vehicle with the air cleaner/filter
off, as flames may be present if the
engine backfires.
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always have
the air cleaner/filter in place when
driving.
Cooling System
The cooling system allows the engine
to maintain the correct working
temperature.
1. Electric Engine Cooling Fan
(Out of View)
2. Coolant Surge Tank and Pressure Cap
{Warning
An underhood electric fan can start
up even when the engine is not
running and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The engine cooling system in the
vehicle are filled with DEX-COOL
engine coolant mixture. This coolant
needs to be checked and changed at

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
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270 VEHICLE CARE
appropriate levels. SeeRecommended
Fluids and Lubricants 0343 and
Maintenance Schedule 0333.
The following explains the cooling
systems and how to check and add
coolant when it is low. If there is a
problem with engine overheating, see
Engine Overheating 0272.
What to Use
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down to
−37 °C (−34 °F), outside
temperature. .
Gives boiling protection up to
129 °C (265 °F), engine
temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.
. Helps keep the proper engine
temperature.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard GMW3420 and
clean, drinkable water. Anything
else can cause damage to the
engine cooling system and the
vehicle, which would not be covered
by the vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or pouring into sewers,
streams, or bodies of water. Have the
coolant changed by an authorized
service center, familiar with legal requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level.
Check to see if coolant is visible in the
coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. If coolant is visible but
the coolant level mark is not at or
above the indicated mark, add a
50/50 mixture of clean, drinkable

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
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3. Fill the coolant surge tank withthe proper mixture to the mark
pointed to on the front of the
coolant surge tank.
4. With the coolant surge tank pressure cap off, start the engine
and let it run until you can feel
the upper radiator hose getting
hot. Watch out for the engine
cooling fans. By this time, the
coolant level inside the coolant
surge tank may be lower. If the
level is lower, add more of the
proper mixture to the coolant
surge tank until the level reaches
the mark pointed to on the front
of the coolant surge tank.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
Engine Overheating
The vehicle has several indicators to
warn of the engine overheating.
There is an engine coolant
temperature gauge on the instrument
cluster. See Engine Coolant Temperature
Gauge 0117. The vehicle may also
display a message on the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears, get
service help right away. See Roadside
Service 0353.
If the decision is made to lift the
hood, make sure the vehicle is parked
on a level surface. Then check to see if
the engine cooling fan is running.
If the engine is overheating, the fan should be running. If it is not, do not
continue to run the engine. Have the
vehicle serviced.
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all coolant
and can damage the system and
vehicle. Have any leaks fixed
right away.
If Steam Is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure cap,
even a little, can cause them to
come out at high speed and you
could be burned. Never turn the cap
when the cooling system, including
the pressure cap, is hot. Wait for
the cooling system and pressure
cap to cool.

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VEHICLE CARE 273
If No Steam Is Coming from the
Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen or
heard, the problem may not be too
serious. Sometimes the engine can get
a little too hot when the vehicle:
.Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the engine coolant temperature
gauge is no longer in the overheated
area or the engine coolant
temperature warning light no longer
displays, the vehicle can be driven. Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
distance from the vehicle in front.
If the warning does not come back on,
continue to drive normally and have
the cooling system checked for proper
fill and function.
If the warning continues, pull over,
stop, and park the vehicle right away.
If there is no sign of steam, idle the
engine for three minutes while parked.
If the warning is still displayed, turn
off the engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an area
where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
The appropriate message will appear
in the Driver Information Center (DIC)
when the fluid level is low.
Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full. See
Engine Compartment
Overview 0263 for reservoir location.
Caution
.
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
(Continued)