
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
298 VEHICLE CARE
Before using cleaners, read and follow
all safety instructions on the label.
While cleaning the interior, open the
doors and windows to get proper
ventilation.
To prevent damage, do not clean the
interior using the following cleaners
or techniques:
.Never use a razor or any other
sharp object to remove soil from
any interior surface.
. Never use a brush with stiff
bristles.
. Never rub any surface aggressively
or with too much pressure.
. Do not use laundry detergents or
dishwashing soaps with
degreasers. For liquid cleaners, use
approximately 20 drops per 3.8 L
(1 gal) of water. A concentrated
soap solution will create streaks
and attract dirt. Do not use
solutions that contain strong or
caustic soap.
. Do not heavily saturate the
upholstery when cleaning. .
Do not use solvents or cleaners
containing solvents.
Interior Glass
To clean, use a terry cloth fabric
dampened with water. Wipe droplets
left behind with a clean dry cloth.
If necessary, use a commercial glass
cleaner after cleaning with plain water.
Caution
To prevent scratching, never use
abrasive cleaners on automotive
glass. Abrasive cleaners or
aggressive cleaning may damage
the rear window defogger.
Cleaning the windshield with water
during the first three to six months of
ownership will reduce tendency to fog.
Speaker Covers
Vacuum around a speaker cover
gently, so that the speaker will not be
damaged. Clean spots with water and
mild soap.
Coated Moldings
Coated moldings should be cleaned.
. When lightly soiled, wipe with a
sponge or soft, lint-free cloth
dampened with water.
. When heavily soiled, use warm
soapy water.
Fabric/Carpet/Suede
Start by vacuuming the surface using
a soft brush attachment. If a rotating
vacuum brush attachment is being
used, only use it on the floor carpet.
Before cleaning, gently remove as
much of the soil as possible:
.
Gently blot liquids with a paper
towel. Continue blotting until no
more soil can be removed.
. For solid soils, remove as much as
possible prior to vacuuming.
To clean: 1. Saturate a clean, lint-free colorfast cloth with water.
Microfiber cloth is recommended
to prevent lint transfer to the
fabric or carpet.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
304 SERVICE AND MAINTENANCE
since the last service. Reset the oil life
system when the oil is changed. See
Engine Oil Life System0243.
Air Conditioning Desiccant
(Replace Every Seven Years)
The air conditioning system requires
maintenance every seven years. This
service requires replacement of the
desiccant to help the longevity and
efficient operation of the air
conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km
(7,500 mi)
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0281. .
Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0241
and
Engine Oil Life System 0243.
. Inspect the engine air cleaner
filter. See Engine Air Cleaner/Filter
0 245.
. Check engine coolant level. See
Cooling System 0246.
. Check windshield washer fluid
level. See Washer Fluid 0252.
. Check tire inflation pressures. See
Tire Pressure 0275.
. Inspect tire wear. See Tire
Inspection 0280.
. Visually check for fluid leaks.
. Inspect brake system. See Exterior
Care 0293. .
Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0293.
. Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.
. Visually inspect halfshafts and
drive shafts for excessive wear,
lubricant leaks, and/or damage
including: tube dents or cracks,
constant velocity joint or universal
joint looseness, cracked or missing
boots, loose or missing boot
clamps, center bearing excessive
looseness, loose or missing
fasteners, and axle seal leaks.
. Check restraint system
components. See Safety System
Check 050.
. Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for loose
or damaged parts.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
SERVICE AND MAINTENANCE 307
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(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.

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
CONNECTED SERVICES 343
using the myCadillac mobile app,
or by contacting an OnStar Advisor.
On some vehicles, Wi-Fi can also be
managed from the Wi-Fi
Hotspot menu.
MyCadillac Mobile App (If Available)
Download the myCadillac mobile app
to compatible Apple and Android
smartphones. Cadillac users can
access the following services from a
smartphone:
.Remotely start/stop the vehicle,
if factory-equipped.
. Lock/unlock doors, if equipped
with automatic locks.
. Activate the horn and lamps.
. Check the vehicle’s fuel level, oil
life, or tire pressure,
if factory-equipped with the Tire
Pressure Monitor System.
. Send destinations to the vehicle.
. Locate the vehicle on a map (U.S.
market only). .
Turn the vehicle's Wi-Fi hotspot
on/off, manage settings, and
monitor data consumption,
if equipped.
. Locate a dealer and schedule
service.
. Request Roadside Service.
. Set a parking reminder with pin
drop, take a photo, make a note,
and set a timer.
. Connect with Cadillac on social
media.
Features are subject to change. For
myCadillac mobile app information
and compatibility, see my.cadillac.com.
An active OnStar or connected service
plan may be required. A compatible
device, factory-installed remote start,
and power locks are required. Data
rates apply. See www.onstar.com for
details and system limitations.
Remote Services
Contact an OnStar Advisor to unlock
the doors or sound the horn and flash
the lamps.
Marketplace
OnStar Advisors can provide offers
from restaurants and retailers on your
route, help locate hotels, or book a
room. These services vary by market.
Diagnostics
By monitoring and reporting on the
vehicle’s key systems, OnStar
Advanced Diagnostics, if equipped,
provides a way to keep up on
maintenance. Capabilities vary by
model. See www.onstar.com for details
and system limitations. Features are
subject to change. For updates on
feature capabilities, see
my.cadillac.com. Message and data
rates may apply.

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

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
INDEX 349
K
Keyless EntryRemote (RKE) System . . . . . . . . . . . . . . . 8
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
L
Labeling, Tire Sidewall . . . . . . . . . . . . . 270
Lamps Cornering . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Courtesy . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Daytime Running (DRL) . . . . . . . . . . 127
Dome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Exterior Controls . . . . . . . . . . . . . . . . . . 125
Exterior Lamps Off Reminder . . . . 127
Exterior Lighting BatterySaver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
Front Turn Signal . . . . . . . . . . . . . . . . . 259
Malfunction Indicator (Check Engine) . . . . . . . . . . . . . . . . . . . . . . . . . . 100
On Reminder . . . . . . . . . . . . . . . . . . . . . . 108
Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Lane Change Alert (LCA) . . . . . . . . . . . 217
Lane Keep Assist (LKA) . . . . . . . . . . . . 219
Lane Keep Assist Light . . . . . . . . . . . . . 103
Lap-Shoulder Belt . . . . . . . . . . . . . . . . . . . . 47
LATCH System Replacing Parts after a Crash . . . . . . 76 LATCH, Lower Anchors and
Tethers for Children . . . . . . . . . . . . . . . 70
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . 259
Lighting Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Illumination Control . . . . . . . . . . . . . . 129
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Lights Airbag Readiness . . . . . . . . . . . . . . . . . . . 98
Antilock Brake System (ABS)Warning . . . . . . . . . . . . . . . . . . . . . . . . . 103
Automatic Vehicle Hold . . . . . . . . . . 103
Brake System Warning . . . . . . . . . . . 102
Charging System . . . . . . . . . . . . . . . . . . . . 99
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . 100
Cruise Control . . . . . . . . . . . . . . . . . . . . . 108
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Driver Mode Control . . . . . . . . . . . . . . 106
Electric Parking Brake . . . . . . . . . . . . 102
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . 105
Engine Oil Pressure . . . . . . . . . . . . . . . 107
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . 127
High-Beam On . . . . . . . . . . . . . . . . . . . . 107
High/Low Beam Changer . . . . . . . . . 127
Lane Keep Assist . . . . . . . . . . . . . . . . . . 103 Lights (cont'd)
Low Fuel Warning . . . . . . . . . . . . . . . . 107
Seat Belt Reminders . . . . . . . . . . . . . . . . 97
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Service Electric Parking Brake . . . 102
StabiliTrak OFF . . . . . . . . . . . . . . . . . . . 104
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 106
Traction Control System
(TCS)/StabiliTrak . . . . . . . . . . . . . . . . 105
Traction Off . . . . . . . . . . . . . . . . . . . . . . . 104
Limited-Slip Differential . . . . . . . . . . . . 191
Locks Automatic Door . . . . . . . . . . . . . . . . . . . . . 19
Delayed Locking . . . . . . . . . . . . . . . . . . . . 18
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lockout Protection . . . . . . . . . . . . . . . . . 19
Power Door . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Loss of Control . . . . . . . . . . . . . . . . . . . . . . 146
Low Fuel Warning Light . . . . . . . . . . . 107
Low-Profile Tires . . . . . . . . . . . . . . . . . . . . 270
Lower Anchors and Tethers for Children (LATCH System) . . . . . . . . . 70
Lumbar Adjustment . . . . . . . . . . . . . . . . . 36 Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . . 36