2021 CADILLAC XT4 check engine

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
364 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0323.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(4) Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced. (5)
Or every five years, whichever
comes first. See Cooling System0291.
(6) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(7) Replace brake fluid every five
years. See Brake Fluid 0296.
(8) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0299.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0300.
(10) Replace air conditioning
desiccant every seven years.
Special Application
Services
.Severe Commercial Use Vehicles
Only: Lubricate chassis components
every oil change.
.Have underbody flushing service
performed. See "Underbody
Maintenance" in Exterior Care0348.
Additional Maintenance
and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional maintenance
services may be required.
It is recommended that your dealer
perform these services —their trained
dealer technicians know your vehicle
best. Your dealer can also perform a
thorough assessment with a
multi-point inspection to recommend
when your vehicle may need
attention.
The following list is intended to
explain the services and conditions to
look for that may indicate services are
required.
Battery
The 12-volt battery supplies power to
start the engine and operate any
additional electrical accessories.
.To avoid break-down or failure to
start the vehicle, maintain a battery
with full cranking power.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
SERVICE AND MAINTENANCE 365
.Trained dealer technicians have the
diagnostic equipment to test the
battery and ensure that the
connections and cables are
corrosion-free.
Belts
.Belts may need replacing if they
squeak or show signs of cracking or
splitting.
.Trained dealer technicians have
access to tools and equipment to
inspect the belts and recommend
adjustment or replacement when
necessary.
Brakes
Brakes stop the vehicle and are crucial
to safe driving.
.Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping.
.Trained dealer technicians have
access to tools and equipment to
inspect the brakes and recommend
quality parts engineered for the
vehicle. Fluids
Proper fluid levels and approved fluids
protect the vehicle’s systems and
components. See
Recommended Fluids
and Lubricants 0367 for GM approved
fluids.
.Engine oil and windshield washer
fluid levels should be checked at
every fuel fill.
.Instrument cluster lights may come
on to indicate that fluids may be
low and need to be filled.
Hoses
Hoses transport fluids and should be
regularly inspected to ensure that
there are no cracks or leaks. With a
multi-point inspection, your dealer
can inspect the hoses and advise if
replacement is needed.
Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage. The
brake lamps need to be checked
periodically to ensure that they light
when braking.
.With a multi-point inspection, your
dealer can check the lamps and
note any concerns.
Shocks and Struts
Shocks and struts help aid in control
for a smoother ride.
.Signs of wear may include steering
wheel vibration, bounce/sway while
braking, longer stopping distance,
or uneven tire wear.
.As part of the multi-point
inspection, trained dealer
technicians can visually inspect the
shocks and struts for signs of
leaking, blown seals, or damage, and
can advise when service is needed.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
TECHNICAL DATA 371
Vehicle Data
Capacities and Specifications
ApplicationCapacities
Metric English
Air Conditioning Refrigerant For the air conditioning system refrigerant type and charge amount, see the refrigerant label under thehood. See your dealer for more information.
Engine Cooling System* 9.4 L 10.0 qt
Engine Oil with Filter 5.0 L 5.3 qt
Fuel Tank
IFWD 60.2 L 15.9 gal
IAWD 61.7 L 16.3 gal
Wheel Nut Torque 190 Y140 lb ft
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual.
Recheck fluid level after filling.
*Engine cooling system capacity values are based on the entire cooling system and its components.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
CUSTOMER INFORMATION 383
If another party's insurance company
is paying for the repairs, you are not
obligated to accept a repair valuation
based on that insurance company's
collision policy repair limits, as you
have no contractual limits with that
company. In such cases, you can have
control of the repair and parts choices
as long as the cost stays within
reasonable limits.
Publication Ordering
Information
Service Manuals
Service manuals have the diagnosis
and repair information on the engine,
transmission, axle, suspension, brakes,
electrical system, steering system,
body, etc.
Customer Literature
Owner’s manuals are written
specifically for owners and are
intended to provide basic operational
information about the vehicle. The
owner’s manual includes the
Maintenance Schedule for all models.Customer literature publications
available for purchase include owner’s
manuals, warranty manuals, and
portfolios. Portfolios include an
owner’s manual, warranty manual,
if applicable, and zip lock bag or
pouch.
Current and Past Models
Service manuals and customer
literature are available for many
current and past model year GM
vehicles.
To order, call 1-800-551-4123
Monday–Friday, 8:00 a.m.–6:00 p.m.
eastern time
For credit card orders only (VISA,
MasterCard, or Discover), see Helm,
Inc. at: www.helminc.com.
To order by mail, write to:
Helm, Incorporated
Attention: Customer Service
47911 Halyard Drive
Plymouth, MI 48170
Make checks payable in U.S. funds.
Radio Frequency
Statement
This vehicle uses license-exempt
transmitters / receivers / systems that
operate on a radio frequency that
complies with Part 15/Part 18 of the
Federal Communications Commission
(FCC) rules and with Innovation,
Science and Economic Development
(ISED) Canada's license-exempt RSS(s)
/ RSP-100 / ICES-GEN.
Operation is subject to the following
two conditions:
1. The device may not cause harmful interference.
2. The device must accept any interference received, including
interference that may cause
undesired operation of the device.
Changes or modifications to any of
these systems by other than an
authorized service facility could void
authorization to use this equipment.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
388 ONSTAR
.Obtain and customize the Wi-Fi
hotspot name or SSID and
password, if equipped.
Press
Qto 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 Service.
.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 Service, Advisors can
locate a nearby service provider to
help with a flat tire, a battery jump,
or an empty gas tank.
Security
If equipped, OnStar provides these
services:
.With Stolen Vehicle Assistance,
OnStar Advisors can use GPS to
pinpoint the vehicle and help
authorities quickly recover it.
.With Remote Ignition Block,
if equipped, OnStar can block the
engine from being restarted.
.With Stolen Vehicle Slowdown,
if equipped, OnStar can work with
law enforcement to gradually slow
the vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked
and the vehicle alarm sounds, a
notification by text, e-mail, or phone
call will be sent. If the vehicle is
stolen, an OnStar Advisor can work
with authorities to recover the vehicle.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
.Prior to vehicle purchase. PressQ
to set up an account.
.After change in ownership and at
90 days.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
INDEX 395
IndexA
About Driving the Vehicle . . . . . . . . . . . . . 2
Accessories and Modifications . . . . . 283
Accessory Power . . . . . . . . . . . . . . . . . . . . 224
Active Fuel Management . . . . . . . . . . . 225
Adaptive Cruise Control . . . . . . . . . . . . 240
Add-On Electrical Equipment . . . . . . 280
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . 39
Agreements
Trademarks and License . . . . . . . . . 187
Air Cleaner/Filter, Engine . . . . . . . . . . 290
Air Conditioning . . . . . . . . . . . . . . . . . . . . 197
Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . . . 289
Air Filter, Passenger Compartment . . . . . . . . . . . . . . . . . . . . . 201
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
How Does an Airbag Restrain? . . . . 58
Passenger Sensing System . . . . . . . . 60
What Makes an AirbagInflate? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Airbag System (cont'd)
What Will You See after an
Airbag Inflates? . . . . . . . . . . . . . . . . . . 59
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Where Are the Airbags? . . . . . . . . . . . 56
Airbags
Adding Equipment to theVehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Passenger Status Indicator . . . . . . . 104
Readiness Light . . . . . . . . . . . . . . . . . . . 104
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
System Check . . . . . . . . . . . . . . . . . . . . . . 54
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . 25
Alert Lane Change . . . . . . . . . . . . . . . . . . . . . . 263
Rear Pedestrian . . . . . . . . . . . . . . . . . . . 256
Side Blind Zone (SBZA) . . . . . . . . . . 263
All-Season Tires . . . . . . . . . . . . . . . . . . . . . 309
All-Wheel Drive . . . . . . . . . . . . . . . .232, 298
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . 142
Antenna Multi-band . . . . . . . . . . . . . . . . . . . . . . . . 146
Antilock Brake System (ABS) . . . . . . 232 Warning Light . . . . . . . . . . . . . . . . . . . . 108

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
396 INDEX
Appearance CareExterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Apple CarPlay and Android Auto . . . . . . . . . . . . . . . . . . . . . . 175
Armrest Storage . . . . . . . . . . . . . . . . . . . . . . 85
Assistance Systems for Driving . . . . 257
Assistance Systems for Parking and Backing . . . . . . . . . . . . . . . . . . . . . . . 250
Audio Bluetooth . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Auto Stop Stop/Start System . . . . . . . . . . . . . . . . 221
Automatic Dimming Mirrors . . . . . . . . . . . . . . . . . . 29
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . 18
Emergency Braking (AEB) . . . . . . . . 260
Headlamp System . . . . . . . . . . . . . . . . 131
Transmission . . . . . . . . . . . . . . . . . . . . . . 226
Transmission Fluid . . . . . . . . . . . . . . . 289
Automatic Transmission
Manual Mode . . . . . . . . . . . . . . . . . . . . . 231
Avoiding Untrusted Media Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147B
BatteryExterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Power Protection . . . . . . . . . . . . . . . . . . 135
Battery - North America . . . . . .297, 342
Blade Replacement, Wiper . . . . . . . . . 299
Bluetooth Overview . . . . . . . . . . . . . . . . . . . . 170, 171
Bluetooth Audio . . . . . . . . . . . . . . . . . . . . 150
Brake
Electric Boost . . . . . . . . . . . . . . . . . . . . . 232
Parking, Electric . . . . . . . . . . . . . . . . . . 233
System Warning Light . . . . . . . . . . . . 107
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296 Antilock . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Automatic Emergency (AEB) . . . . . 260
Braking System Front Pedestrian (FPB) . . . . . . . . . . . 261
Break-In, New Vehicle . . . . . . . . . . . . . . 219
Bulb Replacement Back-up Lamps . . . . . . . . . . . . . . . . . . . 302
Headlamp Aiming . . . . . . . . . . . . . . . . 301
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . 301
Buying New Tires . . . . . . . . . . . . . . . . . . . 325
C
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
California
Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . 282
California Proposition 65 Warning . . . . . . . . . . . . .282, 297, 342, Back Cover
Canadian Vehicle Owners . . . . . . . . . . . . . 1
Capacities and Specifications . . . . . . 371
Carbon Monoxide Engine Exhaust . . . . . . . . . . . . . . . . . . . 226
Liftgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Winter Driving . . . . . . . . . . . . . . . . . . . . 213
Cargo Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Tie-Downs . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Caution, Danger, and Warning . . . . . . . . 2
Center Console Storage . . . . . . . . . . . . . . 86
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . 328
Charging Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Charging System Light . . . . . . . . . . . . . 105
Check Engine Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . . . . . 105
Child Restraints Infants and Young Children . . . . . . . 67

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
398 INDEX
Door (cont'd)Power Locks . . . . . . . . . . . . . . . . . . . . . . . . 18
Drive Belt Routing, Engine . . . . . . . . . 373
Drive Systems All-Wheel Drive . . . . . . . . . . . . . 232, 298
Driver Teen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184
Driver Assistance Systems . . . . . . . . . 248
Driver Behavior . . . . . . . . . . . . . . . . . . . . . 204
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . . . . . 114
Driver Mode Control . . . . . . . . . . . . . . . . 236
Driver Mode Control Light . . . . . . . . . 111
Driving
Assistance Systems . . . . . . . . . . . . . . . 257
Better Fuel Economy . . . . . . . . . . . . . 205
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . 271
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Environment . . . . . . . . . . . . . . . . . . . . . . 204
Hill and Mountain Roads . . . . . . . . 213
If the Vehicle is Stuck . . . . . . . . . . . . 214
Impaired . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Loss of Control . . . . . . . . . . . . . . . . . . . . 208
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Off-Road Recovery . . . . . . . . . . . . . . . . 207
Vehicle Load Limits . . . . . . . . . . . . . . 215
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . 212 Driving (cont'd)
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Driving the Vehicle . . . . . . . . . . . . . . . . . . . . 2
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . . . . . 197
E
Electric Brake Boost . . . . . . . . . . . . . . . . 232
Electric Parking Brake . . . . . . . . . . . . . . 233
Electric Parking Brake Light . . . . . . . 107
Electrical Equipment, Add-On . . . . . 280
Electrical SystemEngine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Fuses and Circuit Breakers . . . . . . . 303
Instrument Panel Fuse Block . . . . 306
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . 302
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . 290
Check Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . . . . . 105
Compartment Overview . . . . . . . . . . 285
Coolant Temperature Gauge . . . . . 103
Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . 111
Cooling System . . . . . . . . . . . . . . . . . . . 291 Engine (cont'd)
Drive Belt Routing . . . . . . . . . . . . . . . . 373
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Oil Life System . . . . . . . . . . . . . . . . . . . . 288
Oil Pressure Light . . . . . . . . . . . . . . . . . 112
Overheating . . . . . . . . . . . . . . . . . . . . . . . 294
Power Messages . . . . . . . . . . . . . . . . . . 120
Running While Parked . . . . . . . . . . . 226
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Engine Air Filter Life System . . . . . . 289
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . 134
Equipment, Towing . . . . . . . . . . . . . . . . . 277
Event Data Recorders . . . . . . . . . . . . . . 385
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . 134
Extended Parking . . . . . . . . . . . . . . . . . . . 225
Extender, Seat Belt . . . . . . . . . . . . . . . . . . 53
Exterior Lamp Controls . . . . . . . . . . . . 129
Exterior Lamps Off Reminder . . . . . . 131
Exterior Lighting Battery Saver . . . . 135
F
Filter, Engine Air Cleaner . . . . . . . . . . . . . . . . 290
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . 131
Flashers, Hazard Warning . . . . . . . . . . 132
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329 Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 337