wiring CADILLAC XT4 2021 Owner's Manual

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
64 SEATS AND RESTRAINTS
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle should
be serviced. There are parts of the
airbag system in several places around
the vehicle. Your dealer and the
service manual have information
about servicing the vehicle and the
airbag system. To purchase a service
manual, seePublication Ordering
Information 0383.
{Warning
For up to 10 seconds after the
vehicle is turned off and the battery
is disconnected, an airbag can still
inflate during improper service. You
can be injured if you are close to an
airbag when it inflates. Avoid
yellow connectors. They are
probably part of the airbag system.
Be sure to follow proper service
procedures, and make sure the
person performing work for you is
qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet metal
may keep the airbag system from
working properly.
The operation of the airbag system
can also be affected by changing,
including improperly repairing or
replacing, any parts of the following:
.Airbag system, including airbag
modules, front or side impact
sensors, sensing and diagnostic
module, or airbag wiring
.Front seats, including stitching,
seams or zippers
.Seat belts
.Steering wheel, instrument panel,
overhead console, ceiling trim,
or pillar garnish trim
.Inner door seals, including speakers
Your dealer and the service manual
have information about the location of
the airbag modules and sensors, sensing and diagnostic module, and
airbag wiring along with the proper
replacement procedures.
In addition, the vehicle has a
passenger sensing system for the front
outboard passenger position, which
includes sensors that are part of the
passenger seat. The passenger sensing
system may not operate properly if
the original seat trim is replaced with
non-GM covers, upholstery, or trim; or
with GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad or
device, installed under or on top of
the seat fabric, could also interfere
with the operation of the passenger
sensing system. This could either
prevent proper deployment of the
passenger airbag(s) or prevent the
passenger sensing system from
properly turning off the passenger
airbag(s). See
Passenger Sensing
System 060.
If the vehicle has rollover roof-rail
airbags, see Different Size Tires and
Wheels 0326 for additional important
information.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
104 INSTRUMENTS AND CONTROLS
If the front passenger seat belt is
buckled, neither the chime nor the
light comes on.
The front passenger seat belt reminder
light and chime may come on if an
object is put on the seat such as a
briefcase, handbag, grocery bag,
laptop, or other electronic device. To
turn off the reminder light and/or
chime, remove the object from the
seat or buckle the seat belt.
Airbag Readiness Light
This light shows if there is an
electrical problem with the airbag
system. The system check includes
the airbag sensor(s), the passenger
sensing system, the pretensioners, the
airbag modules, the wiring, and the
crash sensing and diagnostic module.
For more information on the airbag
system, seeAirbag System 054.
The airbag readiness light comes on
for several seconds when the vehicle is
started. If the light does not come on
then, have it fixed immediately.
{Warning
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in the
vehicle might not inflate in a crash,
or they could even inflate without a
crash. To help avoid injury, have
the vehicle serviced right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
Passenger Airbag Status
Indicator
The vehicle has a passenger sensing
system. See Passenger Sensing System
0 60 for important safety information.
The overhead console has a passenger
airbag status indicator.
When the vehicle is started, the
passenger airbag status indicator will
light ON and OFF, and the symbols for
on and off, for several seconds as a
system check. Then, after several more
seconds, the status indicator will light
either ON or OFF, and either the
symbol for on or off, to let you know
the status of the front outboard
passenger frontal airbag and knee
airbag.
If the word ON, and the on symbol,
are lit on the passenger airbag status
indicator, it means that the front
outboard passenger frontal airbag and
knee airbag are allowed to inflate.
If the word OFF, and the off symbol,
are lit on the passenger airbag status
indicator, it means that the passenger
sensing system has turned off the
front outboard passenger frontal
airbag and knee airbag.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
DRIVING AND OPERATING 279
Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
connector can be plugged into a
trailer connector available through
your dealer.
Trailer Lamps
Always check all trailer lamps are
working at the beginning of each trip,
and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals will illuminate to indicate
the vehicle is turning, changing lanes,
or stopping. When towing a trailer,
the arrows on the instrument cluster
will illuminate even if the trailer is not
properly connected or the bulbs are
burned out.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a Trailer
Sway Control (TSC) feature. Trailersway is unintended side-to-side
motion of a trailer while towing. If the
vehicle is towing a trailer and the TSC
detects that sway is increasing, the
vehicle brakes are selectively applied
at each wheel, to help reduce
excessive trailer sway. If equipped with
the Integrated Trailer Brake Control
(ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC
may also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning
light will flash on the instrument
cluster. Reduce vehicle speed by
gradually removing your foot from the
accelerator. If trailer sway continues,
StabiliTrak/ESC can reduce engine
torque to help slow the vehicle. TSC
will not function if StabiliTrak/ESC is
turned off. See
Traction Control/
Electronic Stability Control 0235.
{Warning
Trailer sway can result in a crash
and in serious injury or death, even
if the vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing
your foot from the accelerator. Then
pull over to check the trailer and
vehicle to help correct possible
causes, including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. See Towing Equipment
0 277 for trailer ratings and hitch
setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are designed
with stiff sidewalls to help prevent
sway and to support heavy loads.
These features can make it difficult to
determine if the trailer tire pressures
are low only based on a visual
inspection.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
302 VEHICLE CARE
Back-Up Lamps
To replace one of these bulbs:
1. Remove the fasteners to removethe trailer hitch cover. 2. Access the lamp through the
opening in the underbody.
3. Disconnect the electrical connector from the bulb assembly.
4. Turn the bulb socketcounterclockwise and pull the bulb
straight out of the socket.
5. Replace the bulb and reverse Steps 1–4 to reinstall.
Electrical System
Electrical System Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload. When the current electrical load is too
heavy, the circuit breaker opens and
closes, protecting the circuit until the
current load returns to normal or the
problem is fixed. This greatly reduces
the chance of circuit overload and fire
caused by electrical problems.
Fuses and circuit breakers protect
power devices in the vehicle.
Replace a bad fuse with a new one of
the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, the
same amperage fuse can be borrowed.
Choose some feature of the vehicle
that is not needed to use and replace
it as soon as possible.
Headlamp Wiring
An electrical overload may cause the
lamps to go on and off, or in some
cases to remain off. Have the
headlamp wiring checked right away if
the lamps go on and off or remain off.

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
VEHICLE CARE 303
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected from
electrical overload, overload due to
heavy snow or ice may cause wiper
linkage damage. Always clear ice and
heavy snow from the windshield
before using the windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
breakers. This greatly reduces the
chance of damage caused by electrical
problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the(CONTINUED)
Danger (Continued)
specified amperage rating when
replacing fuses and circuit breakers.
Use of an oversized fuse or circuit
breaker can result in a vehicle fire.
You and others could be seriously
injured or killed.
{Warning
Installation or use of fuses that do
not meet GM’s original fuse
specifications is dangerous. The
fuses could fail, and result in a fire.
You or others could be injured or
killed, and the vehicle could be
damaged.
See Accessories and Modifications
0 283 and
General Information 0282. To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace a
bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another
fuse location, if a fuse goes out.
Replace the fuse as soon as possible.
Engine Compartment Fuse
Block
The underhood fuse block is in the
engine compartment, on the driver
side of the vehicle.