service CADILLAC XT4 2021 Repair Manual

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
DRIVING AND OPERATING 261
{Warning
AEB may automatically brake the
vehicle suddenly in situations
where it is unexpected and
undesired. It could respond to a
turning vehicle ahead, guardrails,
signs, and other non-moving
objects. To override AEB, firmly
press the accelerator pedal, if it is
safe to do so.
Intelligent Brake Assist (IBA)
IBA may activate when the brake
pedal is applied quickly by providing a
boost to braking based on the speed
of approach and distance to a vehicle
ahead.
Minor brake pedal pulsations or pedal
movement during this time is normal
and the brake pedal should continue
to be applied as needed. IBA will
automatically disengage only when
the brake pedal is released.
{Warning
IBA may increase vehicle braking in
situations when it may not be
necessary. You could block the flow
of traffic. If this occurs, take your
foot off the brake pedal and then
apply the brakes as needed.
AEB and IBA can be disabled through
vehicle personalization. See “Collision/
Detection Systems” underVehicle
Personalization 0120.
{Warning
Using AEB or IBA while towing a
trailer could cause you to lose
control of the vehicle and crash.
Turn the system to Alert, or if the
vehicle has ACC to Off, when
towing a trailer.
A system unavailable message may
display if:
.The front of the vehicle or
windshield is not clean.
.Heavy rain or snow is interfering
with object detection.
.There is a problem with the
StabiliTrak/Electronic Stability
Control (ESC) system.
The AEB system does not need
service.
Front Pedestrian Braking
(FPB) System
If equipped, the FPB system may help
avoid or reduce the harm caused by
front-end crashes with nearby
pedestrians when driving in a forward
gear. FPB displays an amber indicator,
~, when a nearby pedestrian is
detected ahead. When approaching a
detected pedestrian too quickly, FPB
provides a red flashing alert on the
windshield and rapidly beeps or pulses
the driver seat. FPB can provide a
boost to braking or automatically
brake the vehicle. This system
includes Intelligent Brake Assist (IBA),
and the Automatic Emergency Braking
(AEB) system may also respond to
pedestrians. See Automatic Emergency
Braking (AEB) 0260.
The FPB system can detect and alert
to pedestrians in a forward gear at
speeds between 8 km/h (5 mph) and

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DRIVING AND OPERATING 263
Cruise control may be disengaged
when the Front Pedestrian Alert
occurs.
Automatic Braking
If FPB detects it is about to crash into
a pedestrian directly ahead, and the
brakes have not been applied, FPB
may automatically brake moderately
or brake hard. This can help to avoid
some very low speed pedestrian
crashes or reduce pedestrian injury.
FPB can automatically brake to
detected pedestrians between 8 km/h
(5 mph) and 80 km/h (50 mph).
Automatic braking levels may be
reduced under certain conditions,
such as higher speeds.
If this happens, Automatic Braking
may engage the Electric Parking Brake
(EPB) to hold the vehicle at a stop.
Release the EPB. A firm press of the
accelerator pedal will also release
Automatic Braking and the EPB.
{Warning
FPB may alert or automatically
brake the vehicle suddenly in
situations where it is unexpected
and undesired. It could falsely alert
or brake for objects similar in shape
or size to pedestrians, including
shadows. This is normal operation
and the vehicle does not need
service. To override Automatic
Braking, firmly press the accelerator
pedal, if it is safe to do so.
Automatic Braking can be disabled
through vehicle personalization. See
“Front Pedestrian Detection ”in
“Collision/Detection Systems” under
Vehicle Personalization 0120.
{Warning
Using the Front Pedestrian Braking
system while towing a trailer could
cause you to lose control of the
vehicle and crash. Turn the system
to Alert or Off when towing a
trailer.
Cleaning the System
If FPB does not seem to operate
properly, cleaning the outside of the
windshield in front of the rearview
mirror may correct the issue.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists drivers
with avoiding crashes that occur with
moving vehicles in the side blind
zone, or blind spot areas. 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 that
blind zone. If the turn signal is
activated and a vehicle is also
detected on the same side, the display
will flash as an extra warning not to
change lanes. Since this system is part
of the Lane Change Alert (LCA)
system, read the entire LCA section
before using this feature.
Lane Change Alert (LCA)
If equipped, the LCA system is a
lane-changing aid that assists drivers
with avoiding lane change crashes

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DRIVING AND OPERATING 265
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. When you disable
LCA, SBZA is also disabled. SeeVehicle
Personalization 0120. 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 Care0348.
If the DIC still 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.
Radio Frequency Information
See
Radio Frequency Statement 0383.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid
crashes due to unintentional lane
departures. This system uses a camera
to detect lane markings between
60 km/h (37 mph) and 180 km/h
(112 mph). It may assist by gently
turning the steering wheel if the
vehicle approaches a detected lane
marking. It may also provide a Lane
Departure Warning (LDW) alert if the
vehicle crosses a detected lane
marking. LKA can be overridden by
turning the steering wheel. This
system is not intended to keep the
vehicle centered in the lane. LKA will
not assist and alert if the turn signal
is active in the direction of lane

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DRIVING AND OPERATING 267
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.
Fuel
Top Tier Fuel
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.
Recommended Fuel
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

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268 DRIVING AND OPERATING
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
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, seeProhibited Fuels 0268.
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
An arrow on the fuel gauge indicates
which side of the vehicle the fuel door
is on. See Fuel Gauge 0102.
{Warning
Fuel vapors and fuel fires burn
violently and can cause injury or
death.
Follow these guidelines to help
avoid injuries to you and others:
(Continued)

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274 DRIVING AND OPERATING
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more often
when used to tow trailers. See
Maintenance Schedule 0358. It is
especially important to check the
automatic transmission fluid, engine
oil, axle lubricant, belts, cooling
system, and brake system before and
during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 294.
Trailer Towing
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer for
important information about
towing a trailer with the vehicle.
Trailering is different than just driving
the vehicle by itself. Trailering means
changes in handling, acceleration,
braking, durability, and fuel economy.
Successful, safe trailering takes correct
equipment, and it has to be used
properly.
The following information has many
time-tested, important trailering tips
and safety rules. Many of these are important for your safety and that of
your passengers. Read this section
carefully before pulling a trailer.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades,
outside temperature, dimensions of
the front of the trailer, and how
frequently the vehicle is used to tow a
trailer.
When towing a trailer, the combined
weight of the vehicle, vehicle contents,
trailer, and trailer contents must be
below all of the maximum weight
ratings for the vehicle, including:
.GCWR: Gross Combined Weight
Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight
Rating

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280 DRIVING AND OPERATING
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 blow-outs.
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 blow-outs. Never load
your trailer with more weight than the
tires are designed to support. The load
rating is located 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. SeeMalfunction Indicator
Lamp (Check Engine Light) 0105.
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.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and would (Continued)
Caution (Continued)
not be covered by the vehicle
warranty. Always check with your
dealer before adding electrical
equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see Servicing
the Airbag-Equipped Vehicle 064 and
Adding Equipment to the
Airbag-Equipped Vehicle 064.

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Vehicle Care
General Information
General Information . . . . . . . . . . . . . 282
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 282
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 282
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 283
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 283
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 285
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 286
Engine Oil Life System . . . . . . . . . . . 288
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Engine Air Filter Life System . . . . 289
Engine Air Cleaner/Filter . . . . . . . . . 290
Cooling System . . . . . . . . . . . . . . . . . . . 291
Engine Overheating . . . . . . . . . . . . . . 294
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 295
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 296
Battery - North America . . . . . . . . . 297
All-Wheel Drive . . . . . . . . . . . . . . . . . . 298 Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 298
Wiper Blade Replacement . . . . . . . 299
Windshield Replacement . . . . . . . . 300
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 300
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 301
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 301
LED Lighting . . . . . . . . . . . . . . . . . . . . . 301
Back-Up Lamps . . . . . . . . . . . . . . . . . . . 302
Electrical System
Electrical System Overload . . . . . . 302
Fuses and Circuit Breakers . . . . . . 303
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Instrument Panel Fuse Block . . . . 306
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
All-Season Tires . . . . . . . . . . . . . . . . . . 309
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 310
Summer Tires . . . . . . . . . . . . . . . . . . . . 310
Tire Sidewall Labeling . . . . . . . . . . . 310
Tire Designations . . . . . . . . . . . . . . . . . 312
Tire Terminology and Definitions . . . . . . . . . . . . . . . . . . . . . . 313
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 316 Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . . . . . . 317
Tire Pressure Monitor System . . . 318
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 319
Tire Inspection . . . . . . . . . . . . . . . . . . . 322
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 323
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
Buying New Tires . . . . . . . . . . . . . . . . 325
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 326
Uniform Tire Quality Grading . . . 326
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 328
Wheel Replacement . . . . . . . . . . . . . . 328
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 328
If a Tire Goes Flat . . . . . . . . . . . . . . . . 329
Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 331
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 336
Tire Changing . . . . . . . . . . . . . . . . . . . . . 337
Compact Spare Tire . . . . . . . . . . . . . . 341
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 342

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282 VEHICLE CARE
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . 345
Recreational Vehicle Towing . . . . 345
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . 348
Interior Care . . . . . . . . . . . . . . . . . . . . . . 352
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . 355
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM
parts and GM-trained and supported
service people.
Genuine GM parts have one of these
marks:
California Proposition
65 Warning
{Warning
Most motor vehicles, including this
one, as well as many of its service
parts and fluids, contain and/or
emit chemicals known to the State
of California to cause cancer and
birth defects or other reproductive
harm. Engine exhaust, many parts
and systems, many fluids, and
some component wear by-products
contain and/or emit these
chemicals. For more information go
to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0297 and
Jump Starting - North America 0342
and the back cover.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag initiators,
seat belt pretensioners, and lithium
batteries contained in electronic keys,

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may contain perchlorate materials.
Perchlorate Material–special
handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered by
the vehicle warranty.
Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM certified
parts, including control module or software modifications, is not covered
under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle using
genuine GM Accessories installed by a
dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 064.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have the
proper knowledge, service manual,
tools, or parts. Always follow
owner’s manual procedures and
consult the service manual for your
vehicle before doing any
service work. If doing some of your own service
work, use the proper service manual.
It tells you much more about how to
service the vehicle than this manual
can. To order the proper service
manual, see
Publication Ordering
Information 0383.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 064.
If equipped with remote vehicle start,
open the hood before performing any
service work to prevent remote
starting the vehicle accidentally. See
Remote Vehicle Start 014.
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records 0369.
Caution
Even small amounts of
contamination can cause damage to
vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.