2020 CADILLAC CT4 check engine

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
308 SERVICE AND MAINTENANCE
Maintenance Schedule
Additional Required Services -
Severe12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires, if recommended for the vehicle, and
perform Required Services. (1) Check engine oil level
and oil life percentage. Change engine oil and filter,
if needed.@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Inspect evaporative control system. (3)@ @@
Replace engine air cleaner filter. (4)@@@
Replace spark plugs. Inspect spark plug wires and/or
boots.@ @
Change automatic transmission fluid and filter.@@@
Change transfer case fluid, if equipped with
AWD. (5)@@@
Change rear axle fluid, if equipped with limited slip
differential. (5)@@@
Change rear axle fluid, without limited slip
differential. (5)@ @
Change front axle fluid, if equipped with AWD. (5)@@@
Drain and fill engine cooling system. (6)@
Visually inspect accessory drive belts. (7)@
Replace brake fluid. (8)
Replace windshield wiper blades. (9)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas
struts. (10)@ @
Replace air conditioning desiccant. (11)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
SERVICE AND MAINTENANCE 309
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0281.
(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) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0245. (5)
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.
(6) Or every five years, whichever
comes first. See Cooling System0246.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0253.
(9) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0256.
(10) Or every 10 years, whichever
comes first. See Gas Strut(s)0257.
(11) 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 Care
0 293.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
310 SERVICE AND MAINTENANCE
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.
. 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 0313 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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
TECHNICAL DATA 319
ApplicationCapacities
Metric English
Wheel Nut Torque 140 Y100 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 (0.025–0.030 in)
2.7L L4 Turbo Engine (L3B) LAutomatic0.65–0.75 mm (0.025–0.030 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-13183937) -
2020 - crc - 4/28/20
330 CUSTOMER INFORMATION
Insurance pays the bill for the repair,
but you must live with the repair.
Depending on your policy limits, your
insurance company may initially value
the repair using aftermarket parts.
Discuss this with the repair
professional, and insist on Genuine
GM parts. Remember, if the vehicle is
leased, you may be obligated to have
the vehicle repaired with Genuine GM
parts, even if your insurance coverage
does not pay the full cost.
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,
infotainment manuals, and portfolios.
Portfolios include an owner’s manual,
warranty manual, infotainment
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 has 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 RSP-100 / ICES-GEN.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
344 INDEX
IndexA
Accessories and Modifications . . . . . 235
Accessory Power . . . . . . . . . . . . . . . . . . . . 163
Active Fuel Management . . . . . . . . . . . 167
Adaptive Cruise Control . . . . . . . . . . . . 194
Add-On Electrical Equipment . . . . . . 231
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Additional Maintenance and Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . 36
Thigh Support . . . . . . . . . . . . . . . . . . . . . . 36
Air Cleaner/Filter, Engine . . . . . . . . . . 245
Air Conditioning . . . . . . . . . . . . . . . . . . . . 134
Air Filter, Passenger
Compartment . . . . . . . . . . . . . . . . . . . . . 139
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
How Does an Airbag Restrain? . . . . . 55
Passenger Sensing System . . . . . . . . . 57
What Makes an Airbag Inflate? . . . . 55
What Will You See after anAirbag Inflates? . . . . . . . . . . . . . . . . . . . 56
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Where Are the Airbags? . . . . . . . . . . . . 53 Airbags
Adding Equipment to the
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Passenger Status Indicator . . . . . . . . . 99
Readiness Light . . . . . . . . . . . . . . . . . . . . . 98
Servicing Airbag-Equipped Vehicles . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
System Check . . . . . . . . . . . . . . . . . . . . . . . 51
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . . 22
Alert
Lane Change . . . . . . . . . . . . . . . . . . . . . . 217
Rear Pedestrian . . . . . . . . . . . . . . . . . . . 209
Side Blind Zone (SBZA) . . . . . . . . . . 217
All-Season Tires . . . . . . . . . . . . . . . . . . . . . 268
All-Wheel Drive . . . . . . . . . . . . . . . .178, 255
Antilock Brake System (ABS) . . . . . . 179 Warning Light . . . . . . . . . . . . . . . . . . . . 103
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Assistance Systems for Driving . . . . 210
Assistance Systems for Parking and Backing . . . . . . . . . . . . . . . . . . . . . . . 204
Auto Stop
Stop/Start System . . . . . . . . . . . . . . . . 161
Automatic Dimming Mirrors . . . . . . . . . . . . . . . . . . . 27

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
INDEX 345
Automatic (cont'd)Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Emergency Braking (AEB) . . . . . . . . 213
Headlamp System . . . . . . . . . . . . . . . . 128
Transmission . . . . . . . . . . . . . . . . . 169, 171
Transmission Fluid . . . . . . . . . . . . . . . 244
Vehicle Hold Light . . . . . . . . . . . . . . . . 103
Automatic Transmission Manual Mode . . . . . . . . . . . . . . . . 176, 177
Automatic Vehicle Hold (AVH) . . . . 181
B
Battery Exterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Load Management . . . . . . . . . . . . . . . . 131
Power Protection . . . . . . . . . . . . . . . . . . 132
Battery - North America . . . . . .254, 288
Blade Replacement, Wiper . . . . . . . . . 256
Brake Electric Boost . . . . . . . . . . . . . . . . . . . . . 179
Parking, Electric . . . . . . . . . . . . . . . . . . 179
System Warning Light . . . . . . . . . . . . 102
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252 Antilock . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Braking (cont'd)
Automatic Emergency (AEB) . . . . . 213
Braking System Front Pedestrian (FPB) . . . . . . . . . . . 214
Break-In, New Vehicle . . . . . . . . . . . . . . 157
Bulb Replacement Front Turn Signal Lamps . . . . . . . . 259
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . 258
Headlamp Aiming . . . . . . . . . . . . . . . . 258
Headlamps . . . . . . . . . . . . . . . . . . . . . . . . 258
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . . . . . . . 259
Buying New Tires . . . . . . . . . . . . . . . . . . . 282
C
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . 235
California Proposition 65 Warning . . . . . . . . . . . . .234, 254, 288, Back Cover
Canadian Vehicle Owners . . . . . . . . . . . . . 2
Capacities and Specifications . . . . . . 318
Carbon Monoxide Engine Exhaust . . . . . . . . . . . . . . . . . . . 168
Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Winter Driving . . . . . . . . . . . . . . . . . . . . 152 Cargo
Management System . . . . . . . . . . . . . . . 84
Tie-Downs . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Caution, Danger, and Warning . . . . . . . . 3
Center Console Storage . . . . . . . . . . . . . . 83
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . 286
Charging Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Charging System Light . . . . . . . . . . . . . . 99
Check Engine Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . . . . . 100
Child Restraints Infants and Young Children . . . . . . . . 65
Lower Anchors and Tethers forChildren . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Older Children . . . . . . . . . . . . . . . . . . . . . . 63
Securing . . . . . . . . . . . . . . . . . . . . . . . . .76, 78
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . 260
Cleaning Exterior Care . . . . . . . . . . . . . . . . . . . . . . 293
Interior Care . . . . . . . . . . . . . . . . . . . . . . 297
Climate Control Systems Dual Automatic . . . . . . . . . . . . . . . . . . . 134
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Cluster, Instrument . . . . . . . . . . . . . . . . . . 93
Collision Damage Repair . . . . . . . . . . . 328

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
INDEX 347
Driving (cont'd)Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . . . . . 134
E
Electric Brake Boost . . . . . . . . . . . . . . . . 179
Electric Parking Brake . . . . . . . . . . . . . . 179
Electric Parking Brake Light . . . . . . . 102
Electrical Equipment, Add-On . . . . . 231
Electrical SystemEngine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Fuses and Circuit Breakers . . . . . . . 260
Instrument Panel Fuse Block . . . . 262
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 336
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . 245
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . . . . . 100
Compartment Overview . . . . . . . . . . 238
Coolant Temperature Gauge . . . . . . . 97
Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . 105 Engine (cont'd)
Cooling System . . . . . . . . . . . . . . . . . . . 246
Drive Belt Routing . . . . . . . . . . . . . . . . 320
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Oil Life System . . . . . . . . . . . . . . . . . . . . 243
Oil Pressure Light . . . . . . . . . . . . . . . . . 107
Overheating . . . . . . . . . . . . . . . . . . . . . . . 250
Power Messages . . . . . . . . . . . . . . . . . . 115
Running While Parked . . . . . . . . . . . 168
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . 131
Equipment, Towing . . . . . . . . . . . . . . . . . 230
Event Data Recorders . . . . . . . . . . . . . . 333
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . 131
Extended Parking . . . . . . . . . . . . . . . . . . . 167
Extender, Seat Belt . . . . . . . . . . . . . . . . . . 50
Exterior Lamp Controls . . . . . . . . . . . . 125
Exterior Lamps Off Reminder . . . . . . 127
Exterior Lighting Battery Saver . . . . 132
F
Filter,
Engine Air Cleaner . . . . . . . . . . . . . . . . 245
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . 127
Flashers, Hazard Warning . . . . . . . . . . 128
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Fluid
Automatic Transmission . . . . . . . . . 244
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Washer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Folding Mirrors . . . . . . . . . . . . . . . . . . . . . . 26
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
Frequency Statement Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Front Pedestrian Braking (FPB) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214
Front Seats Heated and Ventilated . . . . . . . . . . . . . 40
Front Turn Signal Lamps . . . . . . . . . . 259
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Economy, Driving for Better . . . . . 142
Filling a Portable Fuel
Container . . . . . . . . . . . . . . . . . . . . . . . . 224
Filling the Tank . . . . . . . . . . . . . . . . . . . 222
Foreign Countries . . . . . . . . . . . . . . . . . 222
Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Low Fuel Warning Light . . . . . . . . . 107
Management, Active . . . . . . . . . . . . . . 167
Prohibited Fuels . . . . . . . . . . . . . . . . . . 222
Recommended . . . . . . . . . . . . . . . . . . . . 221
Top Tier . . . . . . . . . . . . . . . . . . . . . . . . . . . 221