2023 CADILLAC XT4 warning light

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
Vehicle Care 345
Brake Fluid
The brake master cylinder
reservoir is filled with GM
approved DOT 4 brake fluid as
indicated on the reservoir cap.
See Engine Compartment
Overview0331 for the
location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) 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
hydraulic system. Have the
brake 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 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 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 (Continued)
Warning (Continued)
damaged. Add brake fluid
only when work is done on
the brake hydraulic system.
When the brake fluid falls to a
low level, the brake warning
light comes on. See Brake
System Warning Light 0128.
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
0 425.
What to Add
Use only GM approved DOT 4
brake fluid from a clean, sealed
container. See Recommended
Fluids and Lubricants 0429.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
364 Vehicle Care
Fuses UsageF41 BCM 1 SS –Body
Control Module 1
(Stop/Start) –LED
Indicator Lighting
Control, Accessory
LED Control,
Run-Start LED
Control, Ambient
Lighting LED
Control 2, Liftgate
Latch Motor Control
Signal, Rear Wiper
Control Signal, High
Beam Lamp Control
(Direct Drive), Rear
Fog LED Lamp
Control Signal,
Windshield Washer
Pump Motor Control
Signal, Run/Crank
Relay Control Signal,
ECM/TCM ACC
Wakeup Control
Signal, Left Rear Turn
Control Signal, Rear
Wiper Wash Pump
Control Signal, Brake
Pedal Apply Signal Fuses Usage
F42 RDO –Radio
F43 APO CNSL –Console
Auxiliary Power
Outlet (Circuit
Breaker)
–
F44 Spare –
Relay Usage K1 –
K2 RAP/ACCY
–
Retained
Accessory Power
K3 Content Theft
–
Not Used
K4 –
K5 –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
flexing. There could be
a blowout and a serious
crash. See Vehicle Load
Limits0242.
(Continued)

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
376 Vehicle Care
reached the level to trigger
illumination of the TPMS low
tire pressure telltale.
Your vehicle has also been
equipped with a TPMS
malfunction indicator to
indicate when the system is
not operating properly. The
TPMS malfunction indicator is
combined with the low tire
pressure telltale. When the
system detects a malfunction,
the telltale will flash for
approximately one minute and
then remain continuously
illuminated. This sequence will
continue upon subsequent
vehicle start-ups as long as
the malfunction exists.
When the malfunction
indicator is illuminated, the
system may not be able to
detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a
variety of reasons, including
the installation of replacement
or alternate tires or wheels on
the vehicle that prevent theTPMS from functioning
properly. Always check the
TPMS malfunction telltale
after replacing one or more
tires or wheels on your vehicle
to ensure that the
replacement or alternate tires
and wheels allow the TPMS to
continue to function properly.
See Tire Pressure Monitor
Operation
0376.
See Radio Frequency
Statement 0446.
Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System
(TPMS). The TPMS is designed
to warn the driver when a low
tire pressure condition exists.
TPMS sensors are mounted
onto each tire and wheel
assembly, excluding the spare
tire and wheel assembly. The
TPMS sensors monitor the air
pressure in the tires and transmit the tire pressure
readings to a receiver located
in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low tire
pressure warning light 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.
See Vehicle Load Limits
0242.
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.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
Vehicle Care 377
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)0136.
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 0242, for an
example of the Tire and
Loading Information label and
its location. Also see Tire
Pressure 0372. The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection
0380, Tire
Rotation 0381, and Tires
0 364.
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.
Factory-installed Tire Inflator
Kits use a GM approved liquid
tire sealant. Using
non-approved tire sealants
could damage the TPMS sensors. See Tire Sealant and
Compressor Kit
0390 for
information regarding the
inflator kit materials and
instructions.
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

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
378 Vehicle Care
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 light and the DIC
message should go off after
successfully completing the
sensor matching process.
See "TPMS Sensor Matching
Process" later in this section.
.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
0383.
.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 come on and stay 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 0367 and
Vehicle Load Limits 0242.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
Vehicle Care 379
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.
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
Each TPMS sensor has a
unique identification code. The
identification code needs to be
matched to a new tire/wheel
position after rotating the
vehicle’s tires or replacing one or more of the TPMS sensors.
The TPMS sensor matching
process should also be
performed after replacing a
spare tire with a road tire
containing the TPMS sensor.
The malfunction light and the
DIC message should go off at
the next ignition cycle. The
sensors are matched to the
tire/wheel positions, using a
TPMS relearn tool, in the
following order: driver side
front tire, passenger side front
tire, passenger side rear tire,
and driver side rear. See your
dealer for service or to
purchase a relearn tool.
A TPMS relearn tool can also
be purchased. See Tire
Pressure Monitor Sensor
Activation Tool at www.
gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657).
There are two minutes to
match the first tire/wheel
position, and five minutes
overall to match all four tire/

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
382 Vehicle Care
Reset the Tire Pressure
Monitor System. See Tire
Pressure Monitor
Operation0376.
Check that all wheel nuts
are properly tightened. See
“Wheel Nut Torque” under
Capacities and
Specifications 0433, and
“Removing the Flat Tire and
Installing the Spare Tire”
under Tire Changing 0398.
{Warning
Rust or dirt on a wheel,
or on the parts to which it
is fastened, can cause
wheel nuts to become
loose over time. The
wheel could come off and
cause a crash. When
changing a wheel, remove
any rust or dirt from
places where the wheel
attaches to the vehicle. In
an emergency, a cloth or
(Continued)
Warning (Continued)
paper towel can be used;
however, use a scraper
or wire brush later to
remove all rust or dirt.
Lightly coat the inner
diameter of the wheel hub
opening with wheel bearing
grease after a wheel
change or tire rotation to
prevent corrosion or rust
buildup.
{Warning
Do not apply grease to
the wheel mounting
surface, wheel conical
seats, or the wheel nuts
or bolts. Grease applied
to these areas could
cause a wheel to become
loose or come off,
resulting in a crash.
When It Is Time for
New Tires
Factors, such as maintenance,
temperatures, driving speeds,
vehicle loading, and road
conditions affect the wear
rate of the tires.
Treadwear indicators are one
way to tell when it is time for
new tires. Treadwear
indicators appear when the
tires have only 1.6 mm (1/16 in)
or less of tread remaining. See
Tire Inspection 0380 and
Tire Rotation 0381.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16412876) - 2023 - CRC - 3/25/22
Vehicle Care 385
range, speed rating, and
construction (radial) as the
original tires.
The Tire and Loading
Information label indicates
the original equipment tires
on the vehicle. See Vehicle
Load Limits0242.
Different Size Tires
and Wheels
If wheels or tires are installed
that are a different size than
the original equipment wheels
and tires, vehicle performance,
including its braking, ride and
handling characteristics,
stability, and resistance to
rollover may be affected. If the
vehicle has electronic systems
such as antilock brakes,
rollover airbags, traction
control, electronic stability
control, or All-Wheel Drive, the
performance of these systems
can also be affected.
{Warning
If different sized wheels are
used, there may not be an
acceptable level of
performance and safety if
tires not recommended for
those wheels are selected.
This increases the chance of
a crash and serious injury.
Only use GM specific wheel
and tire systems developed
for the vehicle, and have
them properly installed by a
GM certified technician.
See Buying New Tires 0383
and Accessories and
Modifications 0327.
Uniform Tire Quality
Grading
The following information
relates to the system
developed by the United
States National Highway
Traffic Safety
Administration (NHTSA), which grades tires by
treadwear, traction, and
temperature performance.
This applies only to
vehicles sold in the United
States. The grades are
molded on the sidewalls of
most passenger car tires.
The Uniform Tire Quality
Grading (UTQG) system
does not apply to deep
tread, winter tires, compact
spare tires, tires with
nominal rim diameters of
10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger
cars and light trucks may
vary with respect to these
grades, they must also
conform to federal safety
requirements and
additional General Motors
Tire Performance Criteria
(TPC) standards.