2023 CADILLAC CT4 heating

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
362 Driving and Operating
transmission in P (Park) for a
few minutes before turning
the engine off. If the overheat
warning comes on, see Engine
Overheating0391.
Parking on Hills
{Warning
To prevent serious injury or
death, always park your
vehicle and trailer on a level
surface when possible.
When parking your vehicle and
your trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park)
yet. Turn the wheels into
the curb if facing downhill
or into traffic if facing
uphill.
2. Have someone place chocks under the trailer
wheels. 3. When the wheel chocks
are in place, gradually
release the brake pedal to
allow the chocks to absorb
the load of the trailer.
4. Reapply the brake pedal. Then apply the parking
brake and shift into
P (Park).
5. Release the brake pedal.
Leaving After Parking on
a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into the
desired gear.
.Release the parking
brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance when Trailer
Towing
The vehicle needs service
more often when used to tow
trailers. See Maintenance
Schedule 0469. It is especially
important to check the
automatic transmission fluid,
engine oil, axle lubricant, belts,
cooling system, and brake
system before and during
each trip.
Check periodically that all nuts
and bolts on the trailer hitch
are tight.
Engine Cooling when
Trailer Towing
The cooling system may
temporarily overheat during
severe operating conditions.
See Engine Overheating 0391.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
368 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . 369
California PerchlorateMaterials
Requirements . . . . . . . . . . . . . 370
Accessories and Modifications . . . . . . . . . . . . . 370
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . 370
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 373
Engine Oil . . . . . . . . . . . . . . . . . . . . 378
Engine Oil Life System . . . 381
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Hydraulic Clutch . . . . . . . . . . . 383
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 383
Engine Air Cleaner/ Filter . . . . . . . . . . . . . . . . . . . . . . . . . 384
Cooling System . . . . . . . . . . . . 386
Engine Overheating . . . . . . . 391 Washer Fluid . . . . . . . . . . . . . . . . 393
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 393
Brake Pad Life System (If
Equipped) . . . . . . . . . . . . . . . . . . 396
Brake Fluid . . . . . . . . . . . . . . . . . . 398
Battery - North
America . . . . . . . . . . . . . . . . . . . . . 399
All-Wheel Drive . . . . . . . . . . . . 400
Park Brake and P (Park) Mechanism Check . . . . . . . 400
Wiper Blade Replacement . . . . . . . . . . . . . . 401
Windshield Replacement . . . . . . . . . . . . . . 401
Gas Strut(s) . . . . . . . . . . . . . . . . . 402
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . 403
Bulb Replacement
Bulb Replacement . . . . . . . . 403
Halogen Bulbs . . . . . . . . . . . . . . 403
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . 403
LED Lighting . . . . . . . . . . . . . . . . 403
Front Turn Signal Lamps . . . . . . . . . . . . . . . . . . . . . . . 404
Electrical System
Electrical SystemOverload . . . . . . . . . . . . . . . . . . . 404
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 406
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . . 407
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 409
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
All-Season Tires . . . . . . . . . . . . 414
Winter Tires . . . . . . . . . . . . . . . . . 414
Run-Flat Tires . . . . . . . . . . . . . . . 415
Self-Sealing Tires . . . . . . . . . . 415
Low-Profile Tires . . . . . . . . . . 416
Summer Tires . . . . . . . . . . . . . . . 416
Tire Sidewall Labeling . . . . 417
Tire Designations . . . . . . . . . . 418
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 419
Tire Pressure . . . . . . . . . . . . . . . 422
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . 423
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 424

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).