2023 CADILLAC CT4 service

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
370 Vehicle Care
California Perchlorate
Materials
Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt
pretensioners, and lithium
batteries contained in
electronic keys, may contain
perchlorate materials.
Perchlorate Material–special
handling may apply. See
www.dtsc.ca.gov/
hazardouswaste/perchlorate.
Accessories and
Modifications
Adding non-dealer accessories
or making modifications to the
vehicle can affect vehicle
performance and safety,
including such things as
airbags, braking, stability, ride
and handling, emissions
systems, aerodynamics,
durability, Driver Assistance
Systems, and electronic
systems like antilock brakes, traction control, and stability
control. These accessories or
modifications could even
cause malfunction or damage
not covered by the vehicle
warranty.
Damage to suspension
components caused by
modifying vehicle height
outside of factory settings will
not be covered by the vehicle
warranty.
Damage to vehicle
components resulting from
modifications or the
installation or use of non-GM
certified parts, including
control module or software
modifications, is not covered
under the terms of the vehicle
warranty and may affect
remaining warranty coverage
for affected parts.
GM Accessories are designed
to complement and function
with other systems on the
vehicle. See your dealer to
accessorize the vehicle using
genuine GM Accessories
installed by a dealer
technician.
Also, see Adding Equipment to
the Airbag-Equipped Vehicle
0
70.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work
on your vehicle if you do not
have the proper knowledge,
service manual, tools,
or parts. Always follow
owner’s manual procedures
and consult the service
manual for your vehicle
before doing any
service work.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 371
If doing some of your own
service work, use the proper
service manual. It tells you
much more about how to
service the vehicle than this
manual can. To order the
proper service manual, see
Publication Ordering
Information0494.
This vehicle has an airbag
system. Before attempting to
do your own service work, see
Servicing the Airbag-Equipped
Vehicle 070.
If equipped with remote
vehicle start, open the hood
before performing any service
work to prevent remote
starting the vehicle
accidentally. See Remote
Vehicle Start 016.
Keep a record with all parts
receipts and list the mileage
and the date of any service
work performed. See
Maintenance Records 0477.Caution
Even small amounts of
contamination can cause
damage to vehicle systems.
Do not allow contaminants
to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto
engine stop/start, turn the
vehicle off before opening
the hood. If the vehicle is on,
the engine will start when
the hood is opened. You or
others could be injured.
{Warning
Components under the hood
can get hot from running the
engine. To help avoid the
risk of burning unprotected
skin, never touch these
(Continued)
Warning (Continued)
components until they have
cooled, and always use a
glove or towel to avoid
direct skin contact.
Clear any snow from the hood
before opening.
To open the hood:
1. Pull the hood release lever with the
isymbol. It is
on the lower left side of
the instrument panel.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 379
Follow these guidelines:
.To get an accurate reading,
park the vehicle on level
ground. Check the engine oil
level after the engine has
been off for at least two
hours. Checking the engine
oil level on steep grades or
too soon after engine
shutoff can result in
incorrect readings. Accuracy
improves when checking a
cold engine prior to starting.
Remove the dipstick and
check the level.
.If unable to wait two hours,
the engine must be off for at
least 15 minutes if the
engine is warm, or at least
30 minutes if the engine is
not warm. Pull out the
dipstick, wipe it with a clean
paper towel or cloth, then
push it back in all the way.
Remove it again, keeping the
tip down, and check the
level.
When to Add Engine Oil
2.0L and 2.7L L4 Engines
3.6L V6 Engine
If the oil is below the
cross-hatched area at the tip
of the dipstick and the engine
has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then
recheck the level. See
“Selecting the Right Engine
Oil” later in this section for an
explanation of what kind of oil to use. For engine oil
crankcase capacity, see
Capacities and Specifications
0
480.
Caution
Do not add too much oil. Oil
levels above or below the
acceptable operating range
shown on the dipstick are
harmful to the engine. If the
oil level is above the
operating range (i.e., the
engine has so much oil that
the oil level gets above the
cross-hatched area that
shows the proper operating
range), the engine could be
damaged. Drain the excess
oil or limit driving of the
vehicle, and seek a service
professional to remove the
excess oil.
See Engine Compartment
Overview 0373 for the
location of the engine oil
fill cap.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 381
manufacturer's warnings
about the use and disposal of
oil products.
Used oil can be a threat to the
environment. If you change
your own oil, be sure to drain
all the oil from the filter before
disposal. Never dispose of oil
by putting it in the trash or
pouring it on the ground, into
sewers, or into streams or
bodies of water. Recycle it by
taking it to a place that
collects used oil.
Engine Oil Life
System
When to Change
Engine Oil
This vehicle has a computer
system that indicates when to
change the engine oil and
filter. This is based on a
combination of factors which
include engine revolutions,
engine temperature, and miles
driven. Based on driving
conditions, the mileage atwhich an oil change is
indicated can vary
considerably. For the oil life
system to work properly, the
system must be reset every
time the oil is changed.
When the system has
calculated that oil life has been
diminished, it indicates that an
oil change is necessary.
A CHANGE ENGINE OIL
SOON message comes on.
Change the oil as soon as
possible within the next
1 000 km (600 mi). It is
possible that, if driving under
the best conditions, the oil life
system might indicate that an
oil change is not necessary for
up to a year. The engine oil
and filter must be changed at
least once a year and at this
time the system must be
reset. Your dealer has trained
service people who will
perform this work and reset
the system. It is also important
to check the oil regularly over
the course of an oil drain
interval and keep it at the
proper level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km
(3,000 mi) since the last oil
change. Remember to reset
the oil life system whenever
the oil is changed.
How to Reset the Engine
Oil Life System
Reset the system whenever
the engine oil is changed so
that the system can calculate
the next engine oil change. To
reset the system:
1. Using the DIC buttons, display REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
2. Press and hold the thumbwheel on the
steering wheel. When the

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
388 Vehicle Care
.Helps keep the proper
engine temperature.
Caution
Do not use anything other
than a mix of DEX-COOL
coolant that meets GM
Standard GMW3420 and
clean, drinkable water.
Anything else can cause
damage to the engine
cooling system and the
vehicle, which would not be
covered by the vehicle
warranty.
Never dispose of engine
coolant by putting it in the
trash, pouring it on the
ground, or into sewers,
streams, or bodies of water.
Have the coolant changed by
an authorized service center,
familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and
your health.
Checking Coolant
The vehicle must be on a level
surface when checking the
coolant level.
It is normal to see coolant
moving in the upper coolant
hose return line when the
engine is running. It is also
normal to see bubbles
entering the surge tank
through the small hose.
Check to see if coolant is
visible in the coolant surge
tank. If the coolant inside the
coolant surge tank is boiling,
do not do anything else until it
cools down.
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.
Be sure the cooling system is
cool before this is done.

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
390 Vehicle Care
To use this feature:
1. With a cold system, addcoolant to the indicated
line on the surge tank.
2. Replace the pressure cap on the surge tank.
3. Activate the service feature:
3.1. Connect the vehicle to a battery charger.
3.2.Turn the ignition to Service Mode. See
Ignition Positions 0261.
3.3.Turn off the air conditioning. 3.4.Set the parking brake.
3.5.At the same time, press
the accelerator and the
brake pedal for
two seconds, then
release.
3.6.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, allow the Electronic
Control Module (ECM)
to go to sleep, about
two minutes, and
repeat Steps 3.2 –3.6.
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 3.2 –3.6. 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.
2.7L L4 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.
To use this feature:
1. With a cold system unscrew the cooling
system air bleeder cap.
If coolant can be seen
through the bleeder move
to Step 3.

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.