2020 CADILLAC CT4 warning

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 267
FusesUsage
46 –
47 –
48 –
49 Trailer
50 Driver seat
51 Left front/Left rear window
52 Passenger seat
Relays Usage
53 –
54 –
55 RunWheels 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 flexing.
There could be a blowout
and a serious crash. See
Vehicle Load Limits 0154.
(Continued)
Warning (Continued)
.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.
.Worn or old tires can
cause a crash. If the tread
is badly worn,
replace them.
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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268 VEHICLE CARE
Warning (Continued)
.Replace any tires that have
been damaged by impacts
with potholes, curbs, etc.
.Improperly repaired tires
can cause a crash. Only
the 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 0276 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 0268.
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
0 282.
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.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 269
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.
The vehicle also has a Tire Pressure
Monitor System (TPMS) that indicates
a loss of tire pressure in any of the
tires.
{Warning
If the low tire warning light displays
on the instrument cluster, the
handling capabilities will be
reduced during severe maneuvers.
Driving too fast could cause loss of
control and you or others could be
injured. Do not drive over 80 km/h
(50 mph) when the low tire warning
light is displayed. Drive cautiously
and check the tire pressures as
soon as possible.
Run-flat tires can be driven up to
80 km (50 mi) at speeds less than
80km/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 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 up to6 mm (0.25 in) in the tread area. The
tire may lose air pressure if the
sidewall is damaged or the tread
puncture is too large. If the Tire
Pressure Monitor System indicates the
tire pressure is low, inspect the tire for
damage and inflate it to the
recommended pressure. If the tire is
unable to maintain the recommended
pressure, contact the nearest
authorized GM servicing facility
immediately for inspection and repair
or replacement. To locate the nearest
GM servicing facility, call GM
Customer Assistance.
Caution
Do not drive on a deflated
self-sealing tire as this could
damage the tire. Make sure the tire
is inflated to the recommended
pressure or have it immediately
repaired or replaced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 275
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.
.Reduced fuel economy.
Overinflated tires, or tires that
have too much air, can result in:
.Unusual wear.
.Poor handling.
(Continued)
Warning (Continued)
.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
0 154.
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 your tires
once a month or more. How to Check
Use a good quality pocket-type
gauge to check the 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).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to get
the pressure measurement. If the
cold tire inflation pressure
matches the recommended
pressure on the Tire and Loading
Information label, no further
adjustment is necessary.
If the inflation pressure is low,
add air until the recommended
pressure is reached. If the
inflation pressure in high, press
on the metal stem in the center of

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
276 VEHICLE CARE
the tire valve to release air.
Re-check the tire pressure with
the tire gauge.
Put the valve caps back on the
valve stems to keep out dirt and
moisture and prevent leaks. Use
only valve caps designed for the
vehicle by GM. TPMS sensors
could be damaged and would not
be covered by the vehicle
warranty.
Tire Pressure for
High-Speed Operation
{Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts additional
strain on tires. Sustained
high-speed driving causes excessive
heat buildup and can cause sudden
tire failure. This could cause a
crash, and you or others could be
killed. Some high-speed rated tires
require inflation pressure(Continued)
Warning (Continued)
adjustment for high-speed
operation. When speed limits and
road conditions allow the vehicle to
be driven at high speeds, make sure
the tires are rated for high-speed
operation, are in excellent
condition, and are set to the correct
cold tire inflation pressure for the
vehicle load.
Vehicles with 225/45R17 91V or 235/
40R18 91V size tires require inflation
pressure adjustment when driving the
vehicle at speeds of
160 km/h (100 mph) or higher. Set the
cold tire inflation pressure to 280
kPa (41 psi).
Vehicles with 235/40R18 XL 95Y size
tires require inflation pressure
adjustment when driving the vehicle
at speeds of 160 km/h (100 mph) or
higher. Set the cold tire inflation
pressure to 340 kPa (49 psi).
Vehicles with 235/35R19 XL 91V size
tires require inflation pressure
adjustment when driving the vehicle at speeds of 160 km/h (100 mph) or
higher. Set the cold tire inflation
pressure to 320 kPa (46 psi).
Sustained operation at speeds over
160 km/h (100 mph) requires a load
limit of the driver and one passenger,
with no additional cargo. When loaded
above this level, up to the GVW, do
not operate the vehicle above
160 km/h (100 mph).
Return the tires to the recommended
cold tire inflation pressure when
high-speed driving has ended. See
Vehicle Load Limits
0154 and
Tire Pressure 0275.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor the
air pressure in your tires and transmit
tire pressure readings to a receiver
located in the vehicle.
Each tire, including the spare (if
provided), should be checked monthly
when cold and inflated to the

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
278 VEHICLE CARE
When a low tire pressure condition is
detected, the TPMS illuminates the
low tire pressure warning light located
on the instrument cluster. If the
warning light comes on, stop as soon
as possible and inflate the tires to the
recommended pressure shown on the
Tire and Loading Information label.
SeeVehicle Load Limits 0154.
A message to check the pressure in a
specific tire displays in the Driver
Information Center (DIC). The low tire
pressure warning light and the DIC
warning message come on at each
ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire pressure
levels can be viewed. For additional
information and details about the DIC
operation and displays see Driver
Information Center (DIC) 0109.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the air
pressure is getting low and needs to
be inflated to the proper pressure. A Tire and Loading Information label,
attached to your vehicle, shows the
size of the original equipment tires
and the correct inflation pressure for
the tires when they are cold. See
Vehicle Load Limits
0154, for an
example of the Tire and Loading
Information label and its location.
Also see Tire Pressure 0275.
The TPMS can warn about a low tire
pressure condition but it does not
replace normal tire maintenance. See
Tire Inspection 0280, Tire Rotation
0 281 and
Tires 0267.
Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly if
one or more of the TPMS sensors are
missing or inoperable. When the
system detects a malfunction, the low
tire pressure warning light flashes for
about one minute and then stays on
for the remainder of the ignition cycle.
A DIC warning message also displays.
The malfunction light and DIC
warning message come on at each
ignition cycle until the problem is
corrected. Some of the conditions that
can cause these to come on are:
.
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a TPMS
sensor. The malfunction light and
DIC message should go off after
the road tire is replaced and the
sensor matching process is
performed successfully. See “TPMS
Sensor Matching Process ”later in
this section.
. The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The malfunction

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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VEHICLE CARE 279
light and the DIC message should
go off after successfully
completing the sensor matching
process.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See your
dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0282.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly it cannot detect or signal a
low tire pressure condition. See your dealer for service if the TPMS
malfunction light and DIC message
comes on and stays on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure.
When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal
lamp will flash.
When the recommended
pressure is reached, the horn
sounds once and the turn signal
lamp will stop flashing and
briefly turn solid. Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.{Warning
Overinflating a tire could cause the
tire to rupture and you or others
could be injured. Do not exceed the
maximum pressure listed on the
tire sidewall. See
Tire Sidewall
Labeling 0270 and
Vehicle Load Limits 0154.
If the tire is overinflated by more than
35 kPa (5 psi), the horn will sound
multiple times and the turn signal
lamp will continue to flash for several
seconds after filling stops. To release
and correct the pressure, while the
turn signal lamp is still flashing,
briefly press the center of the valve
stem. When the recommended
pressure is reached, the horn
sounds once.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
280 VEHICLE CARE
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are on,
the tire fill alert visual feedback will
not work properly.
The TPMS will not activate the tire fill
alert properly under the following
conditions:
.There is interference from an
external device or transmitter.
. The air pressure from the inflation
device is not sufficient to inflate
the tire.
. There is a malfunction in
the TPMS.
. There is a malfunction in the horn
or turn signal lamps.
. The identification code of the
TPMS sensor is not registered to
the system.
. The battery of the TPMS sensor
is low. If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a tire
pressure gauge.
TPMS Sensor Matching Process
—
Auto Learn Function
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
tires or replacing one or more of the
TPMS sensors. When a tire is
installed, the vehicle must be
stationary for about 20 minutes before
the system recalculates. The following
relearn process takes up to
10 minutes, driving at a minimum
speed of 20 km/h (12 mph). A dash (-)
or pressure value will display in the
DIC. See Driver Information Center
(DIC) 0109. A warning message
displays in the DIC if a problem
occurs during the relearn process.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected for
signs of wear or damage at least
once a month.
Replace the tire if:
.The indicators at three or more
places around the tire can
be seen.
.There is cord or fabric showing
through the tire's rubber.
.The tread or sidewall is
cracked, cut, or snagged deep
enough to show cord or fabric.
.The tire has a bump, bulge,
or split.
.The tire has a puncture, cut,
or other damage that cannot
be repaired well because of the
size or location of the damage.