2021 CADILLAC XT6 warning light

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 303
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 304
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 304
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 305
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 305
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 305
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 308
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 311
Engine Oil Life System . . . . . . . . . . . 313
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Air Filter Life System . . . . 314
Engine Air Cleaner/Filter . . . . . . . . . 315
Cooling System . . . . . . . . . . . . . . . . . . . 316
Engine Overheating . . . . . . . . . . . . . . 320
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 321
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 322 Battery - North America . . . . . . . . . 323
All-Wheel Drive . . . . . . . . . . . . . . . . . . 324
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 324
Wiper Blade Replacement . . . . . . . 325
Windshield Replacement . . . . . . . . 326
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 326
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 327
Bulb Replacement
LED Lighting . . . . . . . . . . . . . . . . . . . . . 327
Electrical System
Electrical System Overload . . . . . . 327
Fuses and Circuit Breakers . . . . . . 328
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Instrument Panel Fuse Block . . . . 332
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
All-Season Tires . . . . . . . . . . . . . . . . . . 337
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 338
Summer Tires . . . . . . . . . . . . . . . . . . . . 338
Tire Sidewall Labeling . . . . . . . . . . . 339 Tire Designations . . . . . . . . . . . . . . . . . 340
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 341
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 343
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 345
Tire Pressure Monitor System . . . 346
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 347
Tire Inspection . . . . . . . . . . . . . . . . . . . 350
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 351
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Buying New Tires . . . . . . . . . . . . . . . . 353
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Uniform Tire Quality Grading . . . 354
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Wheel Replacement . . . . . . . . . . . . . . 356
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 356
If a Tire Goes Flat . . . . . . . . . . . . . . . . 357
Tire Changing . . . . . . . . . . . . . . . . . . . . . 358
Compact Spare Tire . . . . . . . . . . . . . . 364
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 364

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 321
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 0308 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 to freeze
and damage the washer fluid
tank and other parts of the
washer system.
.When using concentrated washer
fluid, follow the manufacturer
instructions for adding water.
.Fill the washer fluid tank only
three-quarters full when it is very
cold. This allows for fluid
expansion if freezing occurs,
which could damage the tank if
it is completely full.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 323
.A fluid leak in the brake hydraulic
system. Have the brake hydraulic
system fixed. With a leak, the
brakes will not work well.
Always clean the brake fluid reservoir
cap and the area around the cap
before removing it.
Do not top off the brake fluid. Adding
fluid does not correct a leak. If fluid is
added when the linings are worn,
there will be too much fluid when
new brake linings are installed. Add or
remove fluid, as necessary, only when
work is done on the brake hydraulic
system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You or
others could be burned, and the
vehicle could be damaged. Add
brake fluid only when work is done
on the brake hydraulic system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning Light
0 117. Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid at
the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule
0380.
What to Add
Use only GM approved DOT 3 brake
fluid from a clean, sealed container.
See Recommended Fluids and
Lubricants 0389.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the paint
finish can be damaged. Immediately
wash off any painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the
cap and do not add fluid.
Refer to the replacement number on
the original battery label when a new
battery is needed. For replacement of
the battery, see your dealer.
The vehicle has an Absorbed Glass
Mat (AGM) 12-volt battery.
Installation of a standard 12-volt
battery will result in reduced 12-volt
battery life.
When using a 12-volt battery charger
on the 12-volt AGM battery, some
chargers have an AGM battery setting
on the charger. If available, use the
AGM setting on the charger, to limit
charge voltage to 14.8 volts.
Stop/Start System
This vehicle has a Stop/Start system
to shut off the engine to help
conserve fuel. See Stop/Start System
0 234.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 347
remain continuously illuminated. This
sequence will continue upon
subsequent vehicle start-ups as long
as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a variety
of reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent the
TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
SeeTire Pressure Monitor Operation
0 347.
See Radio Frequency Statement 0406.Tire Pressure Monitor
Operation
This vehicle may have a Tire Pressure
Monitor System (TPMS). The TPMS is
designed to warn the driver when a
low tire pressure condition exists.
TPMS sensors are mounted onto each
tire and wheel assembly, excluding the
spare tire and wheel assembly. The
TPMS sensors monitor the air
pressure in the tires and transmit the
tire pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition is
detected, the TPMS illuminates the
low tire pressure warning light on the
instrument cluster. If the warning
light comes on, stop as soon as
possible and inflate the tires to the
recommended pressure shown on the
Tire and Loading Information label.
See Vehicle Load Limits 0228. A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC
warning message come on at each
ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire pressure
levels can be viewed. For additional
information and details about the DIC
operation and displays see
Driver
Information Center (DIC) 0124.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the air
pressure is getting low and needs to
be inflated to the proper pressure.
A Tire and Loading Information label,
attached to your vehicle, shows the
size of the original equipment tires
and the correct inflation pressure for
the tires when they are cold. See
Vehicle Load Limits 0228, for an
example of the Tire and Loading
Information label and its location.
Also see Tire Pressure 0343.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
348 VEHICLE CARE
The TPMS can warn about a low tire
pressure condition but it does not
replace normal tire maintenance. See
Tire Inspection0350, Tire Rotation
0 351 and
Tires 0337.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly if
one or more of the TPMS sensors are
missing or inoperable. When the
system detects a malfunction, the low
tire pressure warning light flashes for
about one minute and then stays on
for the remainder of the ignition cycle.
A DIC warning message also displays. The malfunction light and DIC
warning message come on at each
ignition cycle until the problem is
corrected. Some of the conditions that
can cause these to come on are:
.One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The malfunction light and
DIC message should go off after the
road tire is replaced and the sensor
matching process is performed
successfully. See
“TPMS Sensor
Matching Process” later in this
section.
.The TPMS sensor matching process
was not done or not completed
successfully after rotating the tires.
The malfunction light and the DIC
message should go off after
successfully completing the sensor
matching process. See "TPMS
Sensor Matching Process" later in
this section.
.One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and the sensor matching process is
performed successfully. See your
dealer for service.
.Replacement tires or wheels do not
match the original equipment tires
or wheels. Tires and wheels other
than those recommended could
prevent the TPMS from functioning
properly. See
Buying New Tires
0 353.
.Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly it cannot detect or signal a
low tire pressure condition. See your
dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 349
When the low tire pressure warning
light comes on:1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal lamp
will flash.
When the recommended pressure
is reached, the horn sounds once
and the turn signal lamp will stop
flashing and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause the
tire to rupture and you or others
could be injured. Do not exceed the
maximum pressure listed on the
tire sidewall. See Tire Sidewall
Labeling 0339 and
Vehicle Load Limits 0228. If the tire is overinflated by more than
35 kPa (5 psi), the horn will sound
multiple times and the turn signal
lamp will continue to flash for several
seconds after filling stops. To release
and correct the pressure, while the
turn signal lamp is still flashing,
briefly press the center of the valve
stem. When the recommended
pressure is reached, the horn
sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are on,
the tire fill alert visual feedback will
not work properly.
The TPMS will not activate the tire fill
alert properly under the following
conditions:
.There is interference from an
external device or transmitter.
.The air pressure from the inflation
device is not sufficient to inflate
the tire.
.There is a malfunction in the TPMS.
.There is a malfunction in the horn
or turn signal lamps.
.The identification code of the TPMS
sensor is not registered to the
system.
.The battery of the TPMS sensor
is low.
If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a tire
pressure gauge.
TPMS Sensor Matching Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or more
of the TPMS sensors. The TPMS
sensor matching process should also
be performed after replacing a spare
tire with a road tire containing the
TPMS sensor. The malfunction light
and the DIC message should go off at
the next ignition cycle. The sensors
are matched to the tire/wheel
positions, using a TPMS relearn tool,

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
352 VEHICLE CARE
Lightly coat the inner diameter of
the wheel hub opening with wheel
bearing grease after a wheel
change or tire rotation to prevent
corrosion or rust buildup.
{Warning
Do not apply grease to the
wheel mounting surface, wheel
conical seats, or the wheel nuts
or bolts. Grease applied to these
areas could cause a wheel to
become loose or come off,
resulting in a crash.
When It Is Time for New
Tires
Factors, such as maintenance,
temperatures, driving speeds, vehicle
loading, and road conditions affect the
wear rate of the tires.
Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when the
tires have only 1.6 mm (1/16 in) or
less of tread remaining. See Tire
Inspection 0350 and
Tire Rotation 0351 for additional
information.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors including
temperatures, loading conditions, and
inflation pressure maintenance affect
how fast aging takes place. GM
recommends that tires, including the
spare if equipped, be replaced after six years, regardless of tread wear. To
identify the age of a tire, use the tire
manufacture date, which is the last
four digits of the DOT Tire
Identification Number (TIN) molded
into one side of the tire sidewall. The
last four digits of the TIN indicate the
tire manufactured date. The first two
digits represent the week and the last
two digits, the year. For example, the
third week of the year 2020 would
have a 4-digit DOT date of 0320. Week
01 is the first full week (Sunday
through Saturday) of each year.
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow
aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
354 VEHICLE CARE
Warning (Continued)
and cause a crash. Use only
radial-ply tires with the wheels
on the vehicle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H, V,
W, Y and ZR speed rated tires.
Never exceed the winter tires’
maximum speed capability when
using winter tires with a lower
speed rating.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size, load
range, speed rating, and
construction (radial) as the
original tires.
The Tire and Loading Information
label indicates the original
equipment tires on the vehicle.
See Vehicle Load Limits 0228.Different Size Tires and
Wheels
If wheels or tires are installed that are
a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This increases
the chance of a crash and serious
injury. Only use GM specific wheel
and tire systems developed for the
vehicle, and have them properly
installed by a GM certified
technician. See
Buying New Tires 0353 and
Accessories and Modifications 0305.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in the
United States. The grades are
molded on the sidewalls of most
passenger car tires. The Uniform
Tire Quality Grading (UTQG)
system does not apply to deep
tread, winter tires, compact spare
tires, tires with nominal rim
diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they must