heating CADILLAC CT4 2023 User Guide

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 387
3.6L V6 Engine
1. Engine Coolant SurgeTank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan
can start up even when the
engine is not running and
can cause injury. Keep
hands, clothing, and tools
away from any underhood
electric fan.
{Warning
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the
vehicle is filled with
DEX-COOL engine coolant.
See Maintenance Schedule
0469 and
Recommended Fluids and
Lubricants 0474.
The following explains the
cooling system and how to
check and add coolant when it
is low. If there is a problem
with engine overheating, see
Engine Overheating 0391.
What to Use
{Warning
Do not touch heater or
radiator hoses, or other
engine parts. They can be
very hot and can burn you.
Do not run the engine if
there is a leak; all coolant
could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean
drinkable water and
DEX-COOL coolant. This
mixture:
.Gives freezing protection
down to −37 °C (−34 °F),
outside temperature.
.Gives boiling protection up
to 129 °C (265 °F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum
parts.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 391
2. Add coolant through thesurge tank until it is visible
through the air bleeder.
3. Replace the cooling system air bleeder cap.
4. Add coolant to the indicated line on the
surge tank.
5. Replace the pressure cap on the surge tank.
6. Activate the service feature:
6.1. Connect the vehicle to a battery charger.
6.2.Turn the ignition to Service Mode. See
Ignition Positions 0261.
6.3.Turn off the air conditioning.
6.4.Set the parking brake.
6.5.At the same time, press the accelerator and the
brake pedal for
two seconds, then
release. 6.6.At the end of the cycle,
check the coolant level
in the surge tank and
add coolant if it is
below the indicated
line. Turn the ignition
off, carefully remove
the pressure cap, refill
to the indicated line,
replace the pressure
cap, and repeat steps
6.2 –6.6.
Listen for pump activation and
movement of the control
valves while watching the level
of the coolant in the surge
tank. If the tank empties, turn
the ignition off, carefully
remove the pressure cap, refill
to the indicated line, replace
the pressure cap, and repeat
steps 6.2 –6.6.
The fill and air removal
process will run for
approximately 15 minutes.Caution
If the pressure cap is not
tightly installed, coolant loss
and engine damage may
occur. Be sure the cap is
properly and tightly secured.
Engine Overheating
The vehicle has an indicator to
warn of the engine
overheating.
If the decision is made not to
lift the hood when this
warning appears, get service
help right away. See Roadside
Assistance Program 0487.
If the decision is made to lift
the hood, make sure the
vehicle is parked on a level
surface.
Then check to see if the
engine cooling fan is running.
If the engine is overheating,
the fan should be running. If it
is not, do not continue to run
the engine. Have the vehicle
serviced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
406 Vehicle Care
5. Insert the replacementfuse into the empty slot of
the blown fuse.
At the next opportunity, see
your dealer to replace the
blown fuse.
Headlamp Wiring
An electrical overload may
cause the lamps to go on and
off, or in some cases to remain
off. Have the headlamp wiring
checked right away if the
lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats
due to heavy snow or ice, the
windshield wipers will stop.
Wiper function is available
immediately after the wiper
switch is set to off, and back
to on. To protect the wiper motor
from overheating, the wipers
may slow down when the
windshield is dry for a long
period of time. If a period of
dry operation, or little
moisture, exceeds 10 minutes,
the wipers may switch to
intermittent operation, and
remain there. When moisture
is again detected on the
windshield, wiper operation
will return to the operator
selected speed.
Although the circuit is
protected from electrical
overload, overload due to
heavy snow or ice may cause
wiper linkage damage. Always
clear ice and heavy snow from
the windshield before using
the windshield wipers.
If the overload is caused by an
electrical problem and not
snow or ice, be sure to get it
fixed.
Fuses and Circuit
Breakers
The wiring circuits in the
vehicle are protected from
short circuits by a combination
of fuses and circuit breakers.
This greatly reduces the
chance of damage caused by
electrical problems.
{Danger
Fuses and circuit breakers
are marked with
their ampere rating. Do not
exceed the
specified amperage rating
when replacing fuses and
circuit breakers. Use of an
oversized fuse or circuit
breaker can result in a
vehicle fire. You and others
could be seriously injured or
killed.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
410 Vehicle Care
Fuses Usage
1–
2 Heating, Ventilation, and Air Conditioning
Blower
3 –
4 –
5 Theft Deterrent/ Universal Garage Door
Opener/Overhead
Console/Rain Sensor
6 –
Fuses Usage
7 Air Quality Ionizer
8 Heated Steering Wheel
9 –
10 Electronic Steering Column Lock 1
11 –
12 –
13 –
Fuses Usage
14–
15 –
16 –
17 –
18 Display/Infotainment/ USB/Multi-function
Control Module
19 Sensing and Diagnostic Module/
Automatic Occupant
Sensing/Data Link
Connection/Wireless
Charging Module/
Virtual Key Module
20 Power Steering Column Module/
Electronic Steering
Column Lock 2
21 Driver Monitor System/Performance
Data Recorder
22 –
23 –
24 –
25 USB
26 –
27 –
28 –

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 413
Fuses Usage
35 Hands Free ClosureRelease
36 Exterior Lighting Module 2
37 Passenger Memory Seat Module
38 –
39 Right Front/Right Rear Window
40 –
41 –
42 Amplifier
43 Park Assist Module
44 Driver Memory Seat Module
45 OnStar
46 –
47 –
48 –
49 –
50 Driver Seat 51 Left Front/Left Rear Window
52 Passenger Seat
Relays Usage
53 –
54 –
55 Run
Wheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer.
See the warranty manual
for information regarding
the tire warranty and
where to get service. For
additional information refer
to the tire manufacturer.
{Warning
.Poorly maintained and
improperly used tires
are dangerous.
.Overloading the tires
can cause overheating
as a result of too much
(Continued)
Warning (Continued) flexing. There could be
a blowout and a serious
crash. See Vehicle Load
Limits 0255.
.Underinflated tires
pose the same danger
as overloaded tires. The
resulting crash could
cause serious injury.
Check all tires
frequently to maintain
the recommended
pressure. Tire pressure
should be checked
when the tires are cold.
.Overinflated tires are
more likely to be cut,
punctured, or broken by
a sudden impact —such
as when hitting a
pothole. Keep tires at
the recommended
pressure.
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
422 Vehicle Care
and the original equipment
tire size and recommended
inflation pressure. See“Tire
and Loading Information
Label” under Vehicle Load
Limits 0255.
Tire Pressure
Tires need the correct
amount of air pressure to
operate effectively.
{Warning
Neither tire underinflation
nor overinflation is good.
Underinflated tires,
or tires that do not have
enough air, can result in:
.Tire overloading and
overheating, which
could lead to a blowout
.Premature or
irregular wear
.Poor handling
(Continued)
Warning (Continued)
.Reduced fuel economy
for internal combustion
engine vehicles
.Reduced range for
electric vehicles
Overinflated tires, or tires
that have too much air,
can result in:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from
road hazards
The Tire and Loading
Information label on the
vehicle indicates the
original equipment tires
and the correct cold tire
inflation pressures. The
recommended pressure is
the minimum air pressure
needed to support the vehicle's maximum load
carrying capacity. See
Vehicle Load Limits
0255.
How the vehicle is loaded
affects vehicle handling
and ride comfort. Never
load the vehicle with more
weight than it was
designed to carry.
When to Check
Check the pressure of the
tires once a month or more.
How to Check
Use a good quality
pocket-type gauge to
check tire pressure. Proper
tire inflation cannot be
determined by looking at
the tire. Check the tire
inflation pressure when the
tires are cold, meaning the
vehicle has not been driven
for at least three hours or
no more than 1.6 km (1 mi).

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
INDEX 517
MediaAvoiding Untrusted
Devices . . . . . . . . . . . . . . . . . . . . . . 166
Memory Seats . . . . . . . . . . . . . . . . . . . 41
Messages Engine Power . . . . . . . . . . . . . . . 141
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . 140
Vehicle Speed . . . . . . . . . . . . . . . 141
Mirrors Automatic Dimming . . . . . . . . . 30
Automatic DimmingRearview . . . . . . . . . . . . . . . . . . . . . . 31
Convex . . . . . . . . . . . . . . . . . . . . . . . . . 28
Folding . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Heated . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Interior Rearview . . . . . . . . . . . . . 31
Manual Rearview . . . . . . . . . . . . . 31
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Tilt in Reverse . . . . . . . . . . . . . . . . 30
Mode Driver Control . . . . . . . . . . . . . . 292
Monitor System, Tire Pressure . . . . . . . . . . . . . . . . . . . . . 424
Multi-band Antenna . . . . . . . . . . 166
Multi-Point Vehicle Inspection (MPVI) . . . . . . . . . . .472N
NavigationConnected Services . . . . . . 506
Destination . . . . . . . . . . . . . . . . . . . 176
Symbols . . . . . . . . . . . . . . . . . . . . . . . 175
Using the System . . . . . . . . . . 170
New Vehicle Break-In . . . . . . 259
O
Odometer . . . . . . . . . . . . . . . . . . . . . . . .112 Trip . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . . 237
Oil Engine . . . . . . . . . . . . . . . . . . . . . . . . 378
Engine Oil Life System . . . . 381
Pressure Light . . . . . . . . . . . . . . 127
Older Children, Restraints . . . . . . . . . . . . . . . . . . . . . . 72
Online Account . . . . . . . . . . . . . . . 486
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . 498
Additional Information . . . . 501
Overview . . . . . . . . . . . . . . . . . . . . . 499
OnStar Emergency . . . . . . . . . 500
OnStar Security . . . . . . . . . . . . . . 501
Outlets
Power . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Overheating, Engine . . . . . . . . . 391 Overview . . . . . . . . . . . . . . . . . . . . . . . . 155
Instrument Panel . . . . . . . . . . . . . . 5
P
Park
Assist . . . . . . . . . . . . . . . . . . 335, 338
Shifting Into . . . . . . . . . . . 267, 268
Shifting Out of . . . . . . 269, 270
Parking . . . . . . . . . . . . . . . . . . . . . . . . . 270 Brake and P (Park)Mechanism Check . . . . . . . 400
Extended . . . . . . . . . . . . . . . . . . . . . 271
Over Things That Burn . . . 271
Parking or Backing Assistance Systems . . . . . . 335
Passenger Airbag Status Indicator . . . . 117
Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Sensing System . . . . . . . . . . . . . . 66
Pedestrian Ahead
Indicator . . . . . . . . . . . . . . . . . . . . . . . 123
Perchlorate Materials Requirements,
California . . . . . . . . . . . . . . . . . . . . . 370
Performance
Data Recorder (PDR) . . . . . . 192
Shifting Light . . . . . . . . . . . . . . . . 122