2023 CADILLAC CT4 check engine

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Service and Maintenance 473
Exterior Lights
.Visual inspection
Windshield and Wipers
.Visual inspection
Battery
.Battery visual inspection
.Battery test results
.Battery cables and
connections
Systems, Fluids, and
Visible Leak Inspection
.Engine oil
.Transmission
.Drive axle
.Transfer case
.Engine cooling system
.Power steering, if equipped
.Fuel system
.Windshield washer fluid
Tire Inspection
.Tire pressure, tread depth,
and wear
.Rotation, if applicable
.Alignment check, optional
.Reset tire pressure monitor
.Check tire sealant expiration
date, if equipped
.Check spare tire, if equipped
Brakes
.Check brake system
Visible and Functional
Inspections
.Seat belt components
.Exhaust system
.Accelerator pedal
.Passenger compartment air
filter, if equipped
.Engine air filter
.Hoses
.Belts
.Shocks and struts
.Steering components
.Axle boots or driveshaft and
u-joints
.Compartment lift struts,
if equipped
.Floor mats secured, no
interference with pedals
.Horn
.Ignition lock, if equipped
.Starter switch
.Evaporative control system
Lubricate
.Chassis components
Special Application
Services
.Severe Commercial Use
Vehicles Only: Lubricate
chassis components every
oil change.
.Have underbody flushing
service performed. See
"Underbody Maintenance" in
Exterior Care 0455.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Technical Data 481
ApplicationCapacities
Metric English
Rear Axle
IOpen Differential - Small 0.75 L 0.79 qt
IOpen Differential - Large 1.0 L 1.0 qt
IMechanical Limited Slip 1.0 L 1.0 qt
IElectronic Limited Slip (V-Series Blackwing) 1.3 L 1.3 qt
Wheel Nut Torque (M12) 140 Y100 lb ft
Wheel Nut Torque (M14) (V-Series Blackwing) 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.
Engine Specifications
Engine VIN CodeTransmission Spark Plug Gap
2.0L L4 Turbo Engine (LSY) KAutomatic0.65–0.75 mm (0.026–0.030 in)
2.7L L4 Turbo Engine (L3B) LAutomatic0.65–0.75 mm (0.026–0.030 in)
3.6L V6 Twin Turbo Engine (LF4) YAutomatic
Manual 0.75–0.90 mm (0.030–0.035 in)
Spark plug gaps are preset by the manufacturer. Re-gapping the spark plug is not recommended and can damage the
spark plug.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/5/22
494 Customer Information
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/
propulsion, 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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
INDEX 509
IndexA
Accessories andModifications . . . . . . . . . . . . . . . . 370
Accessory Power . . . . . . . . . . . .267
Active Rev Match . . . . . . . . . . . . . . . . . . . 285
Adaptive Cruise Control . . . . . . . . . . . . . . 304
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . . 366
Additional OnStar Information . . . . . . . . 501
Adjustments Lumbar, Front Seats . . . . . . . 40
Thigh Support . . . . . . . . . . . . . . . . 39
Agreements Trademarks andLicense . . . . . . . . . . . . . . . . . . . . . . 215
Air
Cleaner/Filter, Engine . . . . 384
Conditioning . . . . . . . . . . . . . . . . 225
Filter Life System . . . . . . . . . 383
Filter, PassengerCompartment . . . . . . . . . . . . . . 231
Vents . . . . . . . . . . . . . . . . . . . . . . . . . . 230
Airbag System . . . . . . . . . . . . . . . . . 59 Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 Airbag System (cont'd)
How Does an Airbag
Restrain? . . . . . . . . . . . . . . . . . . . . . 64
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . . . . 66
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 63
What Will You See after an Airbag
Inflates? . . . . . . . . . . . . . . . . . . . . . . 64
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . 62
Where Are the Airbags? . . . . . . . . . . . . . . . . . . . . . . . 61
Airbags Adding Equipment to
the Vehicle . . . . . . . . . . . . . . . . . . . 70
Passenger Status Indicator . . . . . . . . . . . . . . . . . . . . . . 117
Readiness Light . . . . . . . . . . . . . 116
Replacing System Parts after a Crash . . . . . . . 72
Servicing Airbag-Equipped
Vehicles . . . . . . . . . . . . . . . . . . . . . . 70
Alarm
Vehicle Security . . . . . . . . . . . . . 24

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
INDEX 511
Bulb Replacement (cont'd)High Intensity
Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . 403
Buying New Tires . . . . . . . . . . . . 432
C
Calibration Compass . . . . . . . . . . . . . . . . . . . . . . 101
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . 370
California Proposition 65 Warning . . . . . . . . . . . . . . . . 1, 447
Camera Rear Vision (RVC) . . . . . . . . . 335
Canadian Vehicle Owners . . . . 2
Capacities and
Specifications . . . . . . . . . . . . . . . 480
Carbon Monoxide Engine Exhaust . . . . . . . . . . . . . 271
Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Winter Driving . . . . . . . . . . . . . . 253
Cargo Management System . . . . . . 96
Tie-Downs . . . . . . . . . . . . . . . . . . . . . 96
Caution, Danger, and Warning . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Center Console
Storage . . . . . . . . . . . . . . . . . . . . . . . . 95
Chains, Tire . . . . . . . . . . . . . . . . . . . 437
Charging System Light . . . . . . . . . . . . . . . . . 117
Wireless . . . . . . . . . . . . . . . . . . . . . . . 102
Check Engine Light
(Malfunction Indicator) . . . . .118
Child Restraints Infants and YoungChildren . . . . . . . . . . . . . . . . . . . . . . . 74
Lower Anchors and Tethers for Children . . . . . . 80
Older Children . . . . . . . . . . . . . . . . 72
Securing . . . . . . . . . . . . . . . . . . 88, 90
Systems . . . . . . . . . . . . . . . . . . . . . . . . 77
Child Safety Locks . . . . . . . . . . . . 22
Circuit Breakers . . . . . . . . . . . . . 406
Cleaning Exterior Care . . . . . . . . . . . . . . . 455
Interior Care . . . . . . . . . . . . . . . . . 461
Climate Control Systems Dual Automatic . . . . . . . . . . . . . 225
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Cluster, Instrument . . . 106, 108
Clutch, Hydraulic . . . . . . . . . . . . 383
Collision Damage Repair . . . 491 Compartments
Storage . . . . . . . . . . . . . . . . . . . . . . . . 94
Compass . . . . . . . . . . . . . . . . . . . . . . . . 101
Competitive Driving Mode . . . . . . . . . . . . . . . . 298
Composite Materials . . . . . . . 260
Compressor Kit, Tire Sealant . . . . . . . . . . . . . . . . . . . . . . . . 439
Connected Services Connections . . . . . . . . . . . . . . . . 507
Diagnostics . . . . . . . . . . . . . . . . . . 508
Navigation . . . . . . . . . . . . . . . . . . . 506
Connections Connected Services . . . . . . 507
Control Traction and
Electronic Stability . . . . . . 290
Control of a Vehicle . . . . . . . . 235
Controls Steering Wheel . . . . . . . . . . . . . 158
Convex Mirrors . . . . . . . . . . . . . . . . 28
Coolant
EngineTemperature
Gauge . . . . . . . . . . . . . . . . . . . 114, 115
Engine Temperature Warning Light . . . . . . . . . . . . . . 124

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
INDEX 513
Driving (cont'd)Loss of Control . . . . . . . . . . . . . 237
Off-Road Recovery . . . . . . . . 237
Track Events and
Competitive . . . . . . . . . . . . . . . 238
Vehicle Load Limits . . . . . . . 255
Wet Roads . . . . . . . . . . . . . . . . . . . 251
Winter . . . . . . . . . . . . . . . . . . . . . . . . 253
Dual Automatic ClimateControl System . . . . . . . . . . . 225
E
ElectricBrake Boost . . . . . . . . . . . . . . . . . 286
Parking Brake . . . . . . . . . . . . . . . 287
Parking Brake Light . . . . . . . . 121
Electrical Equipment, Add-On . . . . . . . 366
System Overload . . . . . . . . . . 404
Electrical System Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . . 407
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . . 406
Instrument Panel
Fuse Block . . . . . . . . . . . . . . . . . 409 Electrical System (cont'd)
Rear Compartment
Fuse Block . . . . . . . . . . . . . . . . . . 411
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . . 500
Engine Air Cleaner/Filter . . . . . . . . . . 384
Air Filter Life System . . . . . 383
Check Light
(Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 118
Compartment
Overview . . . . . . . . . . . . . . . . . . . 373
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . 114, 115
Coolant Temperature Warning Light . . . . . . . . . . . . . . 124
Cooling System . . . . . . . . . . . . 386
Drive Belt Routing . . . . . . . . . 482
Exhaust . . . . . . . . . . . . . . . . . . . . . . . 271
Heater . . . . . . . . . . . . . . . . . . . . . . . . 266
Oil Life System . . . . . . . . . . . . . . 381
Oil Pressure Light . . . . . . . . . . 127
Overheating . . . . . . . . . . . . . . . . . . 391
Power Messages . . . . . . . . . . . 141
Running While Parked . . . . 272
Starting . . . . . . . . . . . . . . . . . . . . . . 263 Entry Lighting . . . . . . . . . . . . . . . . . .151
Equipment, Towing . . . . . . . . . 365
Event Data Recorders . . . . . 497
Exit Lighting . . . . . . . . . . . . . . . . . . . .151
Extended Parking . . . . . . . . . . . . 271
Extender, Seat Belt . . . . . . . . . . . 57
Exterior
Lamp Controls . . . . . . . . . . . . . . 145
Lamps Off Reminder . . . . . . 147
Lighting Battery Saver . . . 153
F
FilterEngine Air Cleaner . . . . . . . . 384
Flash-to-Pass . . . . . . . . . . . . . . . . . . 147
Flashers, Hazard Warning . . . . . . . . . . . . . . . . . . . . . . . 149
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 437
Floor Mats . . . . . . . . . . . . . . . . . . . . . 465
Fluid Automatic
Transmission . . . . . . . . . . . . . . 382
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 398
Washer . . . . . . . . . . . . . . . . . . . . . . . 393
Folding Mirrors . . . . . . . . . . . . . . . . . 29
Forward Collision Alert (FCA)System . . . . . . . . . . . . . . . . . . . . . . 342

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
INDEX 515
HeatedMirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Steering Wheel . . . . . . . . . . . . . . 98
Ventilated Front Seats . . . . 45
Heater Engine . . . . . . . . . . . . . . . . . . . . . . . . 266
Heating . . . . . . . . . . . . . . . . . . . . . . . . . 225
High-Beam On Light . . . . . . . . . 128
High-Speed Operation . . . . . 423
Hill and Mountain Roads . . . . . . . . . . . . . . . . . . . . . . . . . 252
Hill Start Assist (HSA) . . . . . . 289
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
How to Wear Seat Belts Properly . . . . . . . . . . . . . . . . . . . . . . . . . 51
HVAC . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Hydraulic Clutch . . . . . . . . . . . . . 383
I
If the System Needs Service . . . . . . . . . . . . . . . . . . . . . . . . . 184
Ignition Positions . . . . . . . . . . . . . 261
Immobilizer . . . . . . . . . . . . . . . . . . . . . . 27
Indicator Pedestrian Ahead . . . . . . . . . . 123
Vehicle Ahead . . . . . . . . . . . . . . . 123 Indicators
Warning Lights and
Gauges . . . . . . . . . . . . . . . . . . . . . . . 105
Infants and Young Children, Restraints . . . . . . . . . 74
Information Publication Ordering . . . . . 494
Infotainment Using the System . . . . . . . . . . 158
Infotainment System . . . . . . . 498
Inspection Multi-Point Vehicle . . . . . . . . . 472
Instrument Cluster . . . . 106, 108
Instrument Panel Overview . . . . . . . . . . . . . . . . . . . . . . . . . 5
Interior Rearview Mirrors . . . . 31
Introduction . . . . . . . . . . . . . . . . . 2, 155
J
Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 447
K
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8Remote . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Remote Operation . . . . . . . . . . . . 9
L
Labeling, Tire Sidewall . . . . . . 417
LampsCornering . . . . . . . . . . . . . . . . . . . . . 149
Courtesy . . . . . . . . . . . . . . . . . . . . . . 150
Daytime Running (DRL) . . . 147
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Exterior Controls . . . . . . . . . . . 145
Exterior Lamps OffReminder . . . . . . . . . . . . . . . . . . . . 147
Exterior Lighting Battery Saver . . . . . . . . . . . . . . 153
Flash-to-Pass . . . . . . . . . . . . . . . . 147
Front Turn Signal . . . . . . . . . . 404
High/Low Beam Changer . . . . . . . . . . . . . . . . . . . . . 147
Malfunction Indicator (Check Engine) . . . . . . . . . . . . . 118
On Reminder . . . . . . . . . . . . . . . . . 128
Reading . . . . . . . . . . . . . . . . . . . . . . . 150
Lane Change Alert (LCA) . . . . . . . 349
Keep Assist (LKA) . . . . . . . . . . 351
Keep Assist Light . . . . . . . . . . 122
Lap-Shoulder Belt . . . . . . . . . . . . . 54
LATCH System Replacing Parts after aCrash . . . . . . . . . . . . . . . . . . . . . . . . . . 87

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
516 INDEX
LATCH, Lower Anchorsand Tethers for
Children . . . . . . . . . . . . . . . . . . . . . . . . . 80
LED Lighting . . . . . . . . . . . . . . . . . . 403
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Illumination Control . . . . . . . . 150
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Lights Airbag Readiness . . . . . . . . . . . 116
Antilock Brake System
(ABS) Warning . . . . . . . . . . . . . . 121
Automatic Emergency Braking (AEB)
Disabled . . . . . . . . . . . . . . . . . . . . . 123
Automatic Vehicle Hold . . . . . . . . . . . . . . . . 122
Brake System Warning . . . . . . . . . . . . . . . . . . . . . 120
Charging System . . . . . . . . . . . . 117
Check Engine
(Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 118
Cruise Control Light . . . . . . . 128
Door Ajar . . . . . . . . . . . . . . . . . . . . . . 129
Driver Mode Control . . . . . . . 125
Electric Parking Brake . . . . . 121 Lights (cont'd)
Engine Coolant
Temperature
Warning . . . . . . . . . . . . . . . . . . . . . 124
Engine Oil Pressure . . . . . . . . 127
Gauges and Indicators . . . . 105
High-Beam On . . . . . . . . . . . . . . . 128
Lane Keep Assist . . . . . . . . . . . 122
Low Fuel Warning . . . . . . . . . . 127
Performance Shifting . . . . . 122
Seat Belt Reminders . . . . . . 115
Security . . . . . . . . . . . . . . . . . . . . . . . 128
Service Electric Parking Brake . . . . . . . . . . . . . . . 121
StabiliTrak OFF . . . . . . . . . . . . . 124
Tire Pressure . . . . . . . . . . . . . . . . 126
Traction Control System
(TCS)/StabiliTrak . . . . . . . . . . 124
Traction Off . . . . . . . . . . . . . . . . . . 123
Limited-Slip Differential . . . . 301
Locks
Automatic Door . . . . . . . . . . . . . . . 21
Delayed Locking . . . . . . . . . . . . . 20
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Lockout Protection . . . . . . . . . . 21
Power Door . . . . . . . . . . . . . . . . . . . 20
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Loss of Control . . . . . . . . . . . . . . .237
Low Fuel Warning Light . . . . 127
Low-Profile Tires . . . . . . . . . . . . . 416
Lower Anchors and
Tethers for Children
(LATCH System) . . . . . . . . . . . . . 80
Lumbar Adjustment . . . . . . . . . . 40
Front Seats . . . . . . . . . . . . . . . . . . . 40
M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . . 477
Maintenance Schedule . . . . 469 Recommended Fluidsand Lubricants . . . . . . . . . . . 474
Malfunction Indicator Lamp . . . . . . . . . . . . . . .118
Manual Mode . . . . . . . . . . . . . . . . . . . . 280, 281
Transmission . . . . . . . . . . . . . . . 283
Transmission Fluid . . . . . . . . 382
Map Data Updates . . . . . . . . . . . 184
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
Massage Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Matching
Active Rev . . . . . . . . . . . . . . . . . . . 285