2023 CADILLAC CT4 service

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
394 Vehicle Care
{Warning
The brake wear warning
sound means that soon the
brakes will not work well.
That could lead to a crash.
When the brake wear
warning sound is heard,
have the vehicle serviced.
Caution
Continuing to drive with
worn-out brake linings could
result in costly brake repairs.
Properly torqued wheel nuts
are necessary to help prevent
brake pulsation. When tires
are rotated, inspect brake
linings for wear and evenly
tighten wheel nuts in the
proper sequence to torque
specifications. See Capacities
and Specifications 0480.
Brake linings should be
replaced as complete
axle sets.
Brake Squeal and
Brake Dust
Some driving conditions or
climates can cause a brake
squeal when the brakes are
first applied, clearing up
following several applies. This
does not mean something is
wrong with the brakes.
Vehicles equipped with high
performance brake systems
provide superior fade
resistance, but will produce
increased brake squeal and
brake dust on the wheels and
calipers as compared to
standard brake linings. This is
normal.
To help reduce squeal, high
performance brake pads are
treated with an anti-squeal
paste that may need to be
reapplied periodically as part
of normal vehicle maintenance.
The anti-squeal paste will
dissipate over time. Also, the
use of wheel cleaners or
power washers directly on the
brake calipers may remove the anti-squeal paste from the
brake pads. It may be
necessary to reapply the
anti-squeal paste if it is
removed during cleaning.
If brake squeal is excessive,
the anti-squeal paste should
be reapplied. The anti-squeal
paste should always be
reapplied whenever the brake
pads are removed or replaced.
See your dealer for service.
Brake Pedal Travel
See your dealer if the brake
pedal does not return to
normal height, or if there is a
rapid increase in pedal travel.
This could be a sign that brake
service may be required.
Replacing Brake System
Parts
Always replace brake system
parts with new, approved
replacement parts. If this is
not done, the brakes may not
work properly. The braking
performance can change in

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 395
many ways if the wrong brake
parts are installed or if parts
are improperly installed.
The Brake Fade Warning
Assist system is designed for
use with the factory-installed
brake pads or GM approved
replacement pads. If the brake
pads on the vehicle need to be
replaced, use GM-approved
brake pads. If this is not done,
the brake fade warning
system may not function
properly.
High Performance Brake
Lining Car Wash and
Extended Parking Care
If equipped with high
performance brake
components, binding or
clunking may be noticeable
after extended parking or in
cold weather when the brakes
have been wet, such as when
driving in the rain or after a
car wash. The clunking is
normal for brakes with high
performance brake linings and
does not affect the operationof the brakes. When driving,
normal braking will allow for
the brakes to feel smooth and
the clunking to go away. If the
vehicle is washed before
overnight parking or long term
storage, drive it and apply the
brakes several times to
thoroughly dry the brakes.
Brake Rotor Wear
(V-Series Blackwing With
J57 Carbon Ceramic
Rotors)
The V-Series Blackwing with
J57 has carbon ceramic brake
rotors. The rotors should be
visually inspected whenever
the brake pads are replaced.
Carbon ceramic brake rotors
also need to be weighed
before brake pads are
replaced to confirm that the
rotor mass is greater than the
wear-out mass printed on the
rotor. The rotor can be reused
if the weight of the rotor is
above the mass limit. Carbon
ceramic brake rotors
inspection and weighing
methods can be found in the
service manual.
V-Series Blackwing Brake
Burnish Procedure for
Corrosion Cleanup
Corrosion spotting and
grooving on the brake rotor
surface may appear after the
vehicle sits for an extended
period of time, especially in
high humidity. This corrosion
may result in brake pulsation
and noise. To help restore
optimal braking performance
and reduce noise, complete
the following procedure:
Caution
Performing the brake
burnish procedure on a base
brake system can result in
brake damage.
Perform this procedure only
on dry pavement, in a safe
manner, and in compliance

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
402 Vehicle Care
work at all. See your dealer for
proper windshield
replacement.
Acoustic Windshield
The vehicle is equipped with
an acoustic windshield. If the
windshield needs to be
replaced be sure to get an
acoustic windshield so you will
continue to have the benefits
an acoustic windshield can
provide.
Gas Strut(s)
Your vehicle may be equipped
with gas strut(s) to provide
assistance in lifting and
holding open the hood/trunk/
liftgate system in full open
position.
{Warning
If the gas struts that hold
open the hood, trunk, and/or
liftgate fail, you or others
could be seriously injured.
Take the vehicle to your(Continued)
Warning (Continued)
dealer for service
immediately. Visually inspect
the gas struts for signs of
wear, cracks, or other
damage periodically. Check
to make sure the hood/
trunk/liftgate is held open
with enough force. If struts
are failing to hold the hood/
trunk/liftgate, do not
operate. Have the vehicle
serviced.
Caution
Do not apply tape or hang
any objects from gas struts.
Also do not push down or
pull on gas struts. This may
cause damage to the
vehicle.
See Maintenance Schedule
0 469.
Hood
Trunk

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 403
Liftgate
Headlamp Aiming
Front Headlamp
Aiming
Headlamp aim has been preset
and should need no further
adjustment.
If the vehicle is damaged in a
crash, the headlamp aim may
be affected. If adjustment to
the headlamps is necessary,
see your dealer.
Bulb Replacement
For the proper type of
replacement bulbs, or any bulb
changing procedure not listed
in this section, contact your
dealer.
Caution
Do not replace incandescent
bulbs with aftermarket LED
replacement bulbs. This can
cause damage to the vehicle
electrical system.
Halogen Bulbs
{Warning
Halogen bulbs have
pressurized gas inside and
can burst if you drop or
scratch the bulb. You or
others could be injured. Be
sure to read and follow the
instructions on the bulb
package.
High Intensity
Discharge (HID)
Lighting
{Warning
The High Intensity Discharge
(HID) lighting system
operates at a very high
voltage. If you try to service
any of the system
components, you could be
seriously injured. Have your
dealer or a qualified
technician service them.
After an HID headlamp bulb
has been replaced, the beam
might be a slightly different
shade than it was originally.
This is normal.
LED Lighting
This vehicle has several LED
lamps. For replacement of any
LED lighting assembly, contact
your dealer.

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
414 Vehicle Care
Warning (Continued)
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired
tires can cause a crash.
Only your dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires.
.Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.See Tire Pressure for
High-Speed Operation
0
423 for inflation pressure
adjustment for high-speed
driving.
All-Season Tires
This vehicle may come with
all-season tires. These tires
are designed to provide good
overall performance on most
road surfaces and weather
conditions. Original equipment
tires designed to GM's specific
tire performance criteria have
a TPC specification code
molded onto the sidewall.
Original equipment all-season
tires can be identified by the
last two characters of this
TPC code, which will be “MS.”
Consider installing winter tires
on the vehicle if frequent
driving on snow or ice-covered
roads is expected. All-season
tires provide adequate
performance for most winter
driving conditions, but they
may not offer the same level of traction or performance as
winter tires on snow or
ice-covered roads. See Winter
Tires
0414.
Winter Tires
This vehicle was not originally
equipped with winter tires.
Winter tires are designed for
increased traction on snow
and ice-covered roads.
Consider installing winter tires
on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your
dealer for details regarding
winter tire availability and
proper tire selection. Also, see
Buying New Tires 0432.
With winter tires, there may
be decreased dry road
traction, increased road noise,
and shorter tread life. After
changing to winter tires, be
alert for changes in vehicle
handling and braking.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 415
If using winter tires:
.Use tires of the same brand
and tread type on all four
wheel positions.
.Use only radial ply tires of
the same size, load range,
and speed rating as the
original equipment tires.
Winter tires with the same
speed rating as the original
equipment tires may not be
available for H, V, W, Y, and ZR
speed rated tires. If winter
tires with a lower speed rating
are chosen, never exceed the
tire's maximum speed
capability.
Run-Flat Tires
This vehicle, when new, may
have had run-flat tires. There
is no spare tire, no tire
changing equipment, and no
place to store a tire in the
vehicle.
{Warning
While driving with run-flat
tires at a reduced inflation
pressure, avoid making
sudden stops or severe
maneuvers as the handling
capabilities of the tires will
be reduced. Driving too fast
could cause loss of control
and you or others could be
injured. Do not drive over
80 km/h (50 mph) with the
tire operating at low
pressure. Drive cautiously
and check the tire pressure
as soon as possible.
Run-flat tires can be driven up
to 80 km (50 mi) at speeds
less than 80 km/h (50 mph)
after a loss of inflation
pressure has occurred. There
is no need to stop on the side
of the road to change the tire.
The possible driving range
after a pressure loss will vary
based on the vehicle load and
driving conditions. As soon as possible, contact the nearest
authorized GM or run-flat
servicing facility for inspection
and repair or replacement.
When driving on a deflated
run-flat tire, avoid potholes
and other road hazards that
could damage the tire and/or
wheel beyond repair. When a
tire has been damaged, or if
driven any distance while
deflated, check with an
authorized run-flat tire service
center to determine whether
the tire can be repaired or
should be replaced. To
maintain the run-flat feature,
all replacement tires must be
run-flat tires.
To locate the nearest GM or
run-flat servicing facility, call
Customer Assistance.
Self-Sealing Tires
This vehicle may have
self-sealing tires. These tires
have a material inside that can
seal punctures from common
road hazards, such as nails