2023 CADILLAC CT4 engine

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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 393
Washer Fluid
What to Use
When windshield washer fluid
is needed, be sure to read the
manufacturer's instructions
before use. If operating the
vehicle in an area where the
temperature may fall below
freezing, use a fluid that has
sufficient protection against
freezing.
Adding Washer Fluid
Open the cap with the washer
symbol on it. Add washer fluid
until the tank is full. See
Engine Compartment
Overview0373 for reservoir
location.
Caution
.Do not use washer fluid
that contains any type of
water repellent coating.
This can cause the wiper
blades to chatter or skip.
.Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
.Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of
the washer system.
.When using concentrated
washer fluid, follow the
manufacturer instructions
for adding water.
.Fill the washer fluid tank
only three-quarters full
when it is very cold. This
allows for fluid expansion
(Continued)
Caution (Continued)
if freezing occurs, which
could damage the tank if it
is completely full.
Brakes
Disc brake linings, except J57
V-Series Blackwing with
carbon ceramic brakes, have
built-in wear indicators that
make a high-pitched warning
sound when the brake linings
are worn and new linings are
needed. The sound can come
and go or can be heard all the
time when the vehicle is
moving, except when applying
the brake pedal firmly. The
V-Series Blackwing has
electronic pad wear sensors.
See Brake Pad Life System (If
Equipped)0396

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
396 Vehicle Care
with all local and state
ordinances/laws regarding
motor vehicle operation.
Caution
The new vehicle break-in
period should be completed
before performing the brake
burnishing procedure or
damage may occur to the
powertrain/engine. See New
Vehicle Break-In0259.
Caution
Brake fade can occur during
this burnish procedure and
can cause brake pedal travel
and force to increase. This
could extend stopping
distance until the brakes are
fully burnished.
Completing the following
procedure as instructed will
not damage the brakes. The
brake pads may smoke and
produce an odor. The braking
force and pedal travel may increase. After the procedure,
the brake pads may appear
white at the rotor contact.
1. Using the G-Force Gauge in the HUD display, apply
the brakes 10 times
starting at 100 km/h
(60 mph) to 50 km/h
(30 mph) while
decelerating at 0.4g.
SeeHead-Up Display (HUD)
0136. This is a medium
brake application. Drive for
at least 0.5 km (0.3 mi)
between applying the
brakes.
2. If further cleanup of the brake discs is needed,
repeat this procedure with
0.7g applications.
As with all high performance
brake systems, some amount
of brake squeal is normal.
Brake Pad Life
System (If Equipped)
When to Change
Brake Pads
If equipped, this system
estimates the remaining life of
the front and rear brake pads.
Brake Pad Life is displayed in
the Driver Information Center
(DIC), along with a percentage
for each axle. The system
must be reset every time the
brake pads are changed.
When the system has
determined that the brake
pads need to be replaced, a
message displays, which may
include mileage remaining.
Brake pads should always be
replaced as complete
axle sets.
How to Reset the Brake
Pad Life System
The system will automatically
detect when significantly worn
brake pads are replaced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
398 Vehicle Care
Brake Fluid
The brake/clutch master
cylinder reservoir is filled with
GM approved DOT 4 brake
fluid as indicated on the
reservoir cap. See Engine
Compartment Overview0373
for the location of the
reservoir.
Checking Brake Fluid
Place the vehicle in P (Park) or
Neutral with the parking brake
applied if equipped with a
manual transmission. On a
level surface, the brake fluid
level should be between the
minimum and maximum marks
on the brake fluid reservoir. There are only two reasons
why the brake fluid level in the
reservoir may go down:
.Normal brake lining wear.
When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake/
clutch hydraulic system.
Have the brake/clutch
hydraulic system fixed. With
a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area
around the cap before
removing it.
Do not top off the brake/
clutch fluid. Adding fluid does
not correct a leak. If fluid is
added when the linings are
worn, there will be too much
fluid when new brake linings
are installed. Add or remove
fluid, as necessary, only when
work is done on the brake/
clutch hydraulic system.
{Warning
If too much brake fluid is
added, it can spill on the
engine and burn, if the
engine is hot enough. You or
others could be burned, and
the vehicle could be
damaged. Add brake fluid
only when work is done on
the brake/clutch hydraulic
system.
When the brake/clutch fluid
falls to a low level, the brake
warning light comes on. See
Brake System Warning Light
0 120.
Brake fluid absorbs water over
time which degrades the
effectiveness of the brake
fluid. Replace brake fluid at the
specified intervals to prevent
increased stopping distance.
See Maintenance Schedule
0 469.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 399
What to Add
Use only GM approved DOT 4
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants0474.
{Warning
The wrong or contaminated
brake fluid could result in
damage to the brake
system. This could result in
the loss of braking leading to
a possible injury. Always use
the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Immediately wash
off any painted surface.
Battery - North
America
The original equipment battery
is maintenance free. Do not
remove the cap and do not
add fluid.
Refer to the replacement
number shown on the original
battery label when a new
battery is needed.
The vehicle has an Absorbed
Glass Mat (AGM) 12-volt
battery. Installation of a
standard 12-volt battery will
result in reduced 12-volt
battery life.
When using a 12-volt battery
charger on the 12-volt AGM
battery, some chargers have
an AGM battery setting on the
charger. If available, use the
AGM setting on the charger,
to limit charge voltage to
14.8 volts. Follow the charger
manufacturer's instructions. Stop/Start System
This vehicle has a Stop/Start
system to shut off the engine
to help conserve fuel. See
Stop/Start System
0264.
{Warning
WARNING: Battery posts,
terminals and related
accessories can expose you
to chemicals including lead
and lead compounds, which
are known to the State of
California to cause cancer
and birth defects or other
reproductive harm. Wash
hands after handling. For
more information go to
www.P65Warnings.ca.gov.
See the warning on the back
cover.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
400 Vehicle Care
Vehicle Storage
{Warning
Batteries have acid that can
burn you and gas that can
explode. You can be badly
hurt if you are not careful.
See Jump Starting - North
America0447 for tips on
working around a battery
without getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from
the battery to keep the
battery from running down.
Extended Storage: Remove
the black, negative (−) cable
from the battery or use a
battery trickle charger.
All-Wheel Drive
If the vehicle is equipped with
All-Wheel-Drive (AWD), this is
an additional system that
needs lubrication.
Transfer Case
Under normal driving
conditions, transfer case fluid
does not require maintenance
unless there is a fluid leak or
unusual noise. If required, have
the transfer case serviced by
your dealer.
Park Brake and
P (Park) Mechanism
Check
{Warning
When you are doing this
check, the vehicle could
begin to move. You or
others could be injured and
property could be damaged.
Make sure there is room in
front of the vehicle in case it
begins to roll. Be ready to
apply the regular brake at
once should the vehicle
begin to move. Park on a fairly steep hill, with
the vehicle facing downhill.
Keeping your foot on the
regular brake, set the parking
brake.
.To check the parking brake's
holding ability: With the
engine running and the
transmission in N (Neutral),
slowly remove foot pressure
from the regular brake pedal.
Do this until the vehicle is
held by the parking
brake only.
.Automatic transmission
vehicles only: To check the
P (Park) mechanism's holding
ability: With the engine
running, shift to P (Park).
Then release the parking
brake followed by the
regular brake.
Contact your dealer if service
is required.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 405
Replacing a Blown Fuse
1. Turn off the ignition.
2. Locate the fuse puller inthe engine compartment
fuse block.
3. Use the fuse puller toremove the fuse from the
top or side, as shown
above.
4. If the fuse must be replaced immediately,
borrow a replacement fuse
with the same amperage
from the fuse block.
Choose a vehicle feature
that is not needed to
safely operate the vehicle.
Repeat Steps 2-3.