2023 CADILLAC CT4 engine overheat

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
Driving and Operating 269
automatically. You may not
be able to release the EPB
using the EPB switch.
It should automatically
release when the vehicle is
shifted out of P (Park).
Leaving the Vehicle with
the Engine Running
{Warning
It can be dangerous to leave
the vehicle with the engine
running. It could overheat
and catch fire.
It is dangerous to get out of
the vehicle if the vehicle is
not in P (Park) with the
parking brake set. The
vehicle can roll.
Do not leave the vehicle
when the engine is running.
If you have left the engine
running, the vehicle can
move suddenly. You or
others could be injured. To
be sure the vehicle will not(Continued)
Warning (Continued)
move, even when you are on
fairly level ground, always
set the parking brake and
shift to P (Park). See Shifting
Into Park (Mechanical
Shifter)0267 or
Shifting Into Park (Electronic
Shifter) 0268. If you are
towing a trailer, see Driving
Characteristics and Towing
Tips 0358.
If you have to leave the vehicle
with the engine running, be
sure the vehicle is in P (Park)
and the parking brake is set
before you leave it.
If you are towing a trailer and
parking on a hill, see Driving
Characteristics and Towing
Tips 0358.
Shifting out of Park
(Mechanical Shifter)
This vehicle is equipped with
an electronic shift lock release
system. The shift lock release
is designed to prevent
movement of the shift lever
out of P (Park), unless the
ignition is on and the brake
pedal is applied.
The shift lock release is always
functional except in the case
of an uncharged or low
voltage (less than 9 volt)
battery.
If the vehicle has an
uncharged battery or a
battery with low voltage, try
charging or jump starting the
battery. See Jump Starting -
North America 0447 for more
information.
To shift out of P (Park):
1. Apply the brake pedal.
2. Release the parking brake. See Electric Parking Brake
0287.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
Driving and Operating 361
Towing with a Stability
Control System
When towing, the stability
control system might be
heard. The system reacts to
vehicle movement caused by
the trailer, which mainly occurs
during cornering. This is
normal when towing heavier
trailers.
Following Distance
Stay at least twice as far
behind the vehicle ahead as
you would when driving
without a trailer. This can help
to avoid heavy braking and
sudden turns.
Passing
More passing distance is
needed when towing a trailer.
The combination of the vehicle
and trailer will not accelerate
as quickly and is much longer
than the vehicle alone. It is
necessary to go much farther
beyond the passed vehiclebefore returning to the lane.
Pass on level roadways. Avoid
passing on hills if possible.
Backing Up
Hold the bottom of the
steering wheel with one hand.
To move the trailer to the left,
move that hand to the left. To
move the trailer to the right,
move that hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
Caution
Turn more slowly and make
wider arcs when towing a
trailer to prevent damage to
your vehicle. Making very
sharp turns could cause the
trailer to contact the vehicle.
Make wider turns than normal
when towing, so trailer will not
go over soft shoulders, over
curbs, or strike road signs,
trees, or other objects. Always signal turns well in advance.
Do not steer or brake
suddenly.
Driving on Grades
Reduce speed and shift to a
lower gear before starting
down a long or steep downhill
grade. If the transmission is
not shifted down, the brakes
may overheat and result in
reduced braking efficiency.
Vehicles can tow in D (Drive).
Shift the transmission to a
lower gear if the transmission
shifts too often under heavy
loads and/or hilly conditions.
When towing at higher
altitudes, engine coolant will
boil at a lower temperature
than at lower altitudes. If the
engine is turned off
immediately after towing at
high altitude on steep uphill
grades, the vehicle could show
signs similar to engine
overheating. To avoid this, let
the engine run, preferably on
level ground, with the

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 389
If no coolant is visible in the
coolant surge tank, add
coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Warning
Spilling coolant on hot
engine parts can burn you.
Coolant contains ethylene
glycol and it will burn if the
engine parts are hot enough.
{Warning
Plain water, or other liquids
such as alcohol, can boil
before the proper coolant
mixture will. With plain water
or the wrong mixture, the
engine could get too hot but
there would not be an
overheat warning. The
engine could catch fire and
you or others could be
burned.
{Warning
Steam and scalding liquids
from a hot cooling system
are under pressure. Turning
the pressure cap, even a
little, can cause them to
come out at high speed and
you could be burned. Never
turn the cap when the
cooling system, including the
pressure cap, is hot. Wait for
the cooling system and
pressure cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could
cause the engine to
overheat and could cause
system damage. If coolant is
not visible in the surge tank,
contact your dealer.
If no problem is found, check
to see if coolant is visible in
the coolant surge tank.
If coolant is visible but the coolant level is not at or above
the indicated mark, add a
50/50 mixture of clean,
drinkable water and
DEX-COOL coolant at the
coolant surge tank, but be
sure the cooling system,
including the coolant surge
tank pressure cap, is cool
before you do it.2.0L L4 Engine and 3.6L
V6 Engine
Automatic Coolant Service
Fill Instructions
The vehicle is equipped with a
service feature that assists
with filling and removing air
from the cooling system after
service of components or
when coolant is added after
being to low.

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
392 Vehicle Care
Caution
Do not run the engine if
there is a leak in the engine
cooling system. This can
cause a loss of all coolant
and can damage the system
and vehicle. Have any leaks
fixed right away.
If Steam Is Coming from
the Engine Compartment
{Warning
Steam and scalding liquids
from a hot cooling system
are under pressure. Turning
the pressure cap, even a
little, can cause them to
come out at high speed and
you could be burned. Never
turn the cap when the
cooling system, including the
pressure cap, is hot. Wait for
the cooling system and
pressure cap to cool.
If No Steam Is Coming
from the Engine
Compartment
If an engine overheat warning
is displayed but no steam can
be seen or heard, the problem
may not be too serious.
Sometimes the engine can get
a little too hot when the
vehicle:
.Climbs a long hill on a
hot day.
.Stops after high-speed
driving.
.Idles for long periods in
traffic.
If the overheat warning is
displayed with no sign of
steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and
to the highest fan speed.
Open the windows as
necessary. 3. When it is safe to do so,
pull off the road, shift to
P (Park) or N (Neutral) and
let the engine idle.
If the overheat warning no
longer displays, the vehicle
can be driven. Continue to
drive the vehicle slowly for
about 10 minutes. Keep a safe
vehicle distance from the
vehicle in front. If the warning
does not come back on,
continue to drive normally and
have the cooling system
checked for proper fill and
function.
If the warning continues, pull
over, stop, and park the
vehicle right away.
If there is no sign of steam,
idle the engine for
three minutes while parked.
If the warning is still displayed,
turn off the engine until it
cools down.