2021 CADILLAC XT4 trailer

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
278 DRIVING AND OPERATING
Hitch Cover
To remove hitch cover, if equipped:1. Remove the two fasteners on the lower tabs.
2. Pull the lower edge of the cover to about a 45 degree angle.
3. Pull the cover downward to disengage the upper attachments.
To reinstall the hitch cover: 1. Hold cover at a 45 degree angle to the vehicle and push the upper
tabs into the slots in the bumper.
2. Push the bottom of the cover forward until the lower tabs line up
with the lower slots. 3. Snap the hitch cover into place by
pushing the upper corners forward.
4. Reinstall the two fasteners on the lower tabs.
Consider using mechanical sway
controls with any trailer. Ask a
trailering professional about sway
controls or refer to the trailer
manufacturer's recommendations and
instructions.
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to
support loads while towing a trailer.
See Tires 0308 for instructions on
proper tire inflation.
Safety Chains
Always attach chains between the
vehicle and the trailer, and attach the
chains to the holes on the trailer hitch
platform. Instructions about safety
chains may be provided by the hitch
manufacturer or by the trailer
manufacturer. Cross the safety chains under the
tongue of the trailer to help prevent
the tongue from contacting the road if
it becomes separated from the hitch.
Always leave just enough slack so the
combination can turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
Loaded trailers over 450 kg (1,000 lb)
must be equipped with brake systems
and with brakes for each axle. Trailer
braking equipment conforming to
Canadian Standards Association (CSA)
requirement CAN3-D313, or its
equivalent, is recommended.
State or local regulations may require
trailers to have their own braking
system if the loaded weight of the
trailer exceeds certain minimums that
can vary from state to state. Read and
follow the instructions for the trailer
brakes so they are installed, adjusted,
and maintained properly. Never
attempt to tap into your vehicle's
hydraulic brake system. If you do,
both the vehicle anti-lock brakes and
the trailer brakes may not function,
which could result in a crash.

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
280 DRIVING AND OPERATING
Always check all trailer tire pressures
before each trip when the tires are
cool. Low trailer tire pressure is a
leading cause of trailer tire blow-outs.
Trailer tires deteriorate over time. The
trailer tire sidewall will show the week
and year the tire was manufactured.
Many trailer tire manufacturers
recommend replacing tires more than
six years old.
Overloading is another leading cause
of trailer tire blow-outs. Never load
your trailer with more weight than the
tires are designed to support. The load
rating is located on the trailer tire
sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default trailer
tire speed rating is 105 km/h
(65 mph).Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. SeeMalfunction Indicator
Lamp (Check Engine Light) 0105.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle systems.
This could affect vehicle operation
and cause a crash. Such devices
may also access information stored
in the vehicle’s systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and would (Continued)
Caution (Continued)
not be covered by the vehicle
warranty. Always check with your
dealer before adding electrical
equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see Servicing
the Airbag-Equipped Vehicle 064 and
Adding Equipment to the
Airbag-Equipped Vehicle 064.

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
304 VEHICLE CARE
Caution
Do not pull the engine
compartment fuse block lever, since
it is intended only for service
purposes. If pulled, vehicle
malfunction may occur.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.
To remove the fuse block cover, press
the clips on the cover and lift it
straight up.
The vehicle may not be equipped with
all of the fuses, relays, and features
shown.
Fuses Usage
3 Electronic brake control module Fuses
Usage
5 Trailer brake
6 Rear closure

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
VEHICLE CARE 305
FusesUsage
7 Trailer stop/Turn LH
8 Memory seat module
9 Pedestrian friendly alert function
10 Semi-active damping system
11 DC DC Battery 1/2
12 Rear defogger
13 Heated mirror
14 –
15 Passive entry passive start
16 Front wiper
17 Passenger power seat
18 Power liftgate module
19 Driver power seat
21 Sunroof
22 Rear wiper
23 Trailer interface module 2 Fuses
Usage
26 Transmission control module/Ignition
27 Instrument panel body/ Ignition
28 Rear wiper
29 Trailer ignition
30 Malfunction indicator lamp start/stop Trailer
interface module ignition
32 Rear drive control module 1
33 –
34 Handsfree/Window switch
35 Diesel exhaust fuel heater
36 Fuel module
39 Massage
40 Steering column lock
41 –
43 Heated steering wheel Fuses
Usage
44 Seat ventilation/Front heated seat
46 Engine control module/ Ignition
48 Rear drive control module 2
49 Heating ventilation/Air conditioning blower
motor
50 –
51 –
54 –
55 –
56 Starter motor
57 –
58 –
59 High-beam headlamps left/right
60 Trailer interface module 1
61 –
62 –

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
306 VEHICLE CARE
FusesUsage
63 –
65 Air conditioning control
67 –
68 –
69 –
70 Trailer park lamp
72 Starter pinion
75 Engine control module main
76 Powertrain off engine
78 Horn
79 Washer pump
81 Transmission control module/Engine control
module/Cooling pump
82 Nitrogen oxide sensor
83 Ignition coil
84 Powertrain on engine
85 Shunt
86 –
87 Diesel fuel heater 1 Fuses
Usage
88 Aeroshutter
89 Selective catalytic reduction module
92 Trailer stop/Turn right
93 Automatic headlamp leveling/Canister vent
solenoid
95 Smart sensors
96 Diesel fuel heater 2
99 –
Relays Usage
4 –
20 Rear defogger
25 Front wiper control
31 Run/Crank
37 Front wiper speed
42 –
64 Starter motor
66 Powertrain
71 Trailer park lamp Relays
Usage
73 Air conditioning control
80 Starter pinion
90 Powertrain sensor
94 Diesel exhaust fuel heater
98 Diesel fuel heater
Instrument Panel Fuse
Block
The instrument panel fuse block is on
the driver side of the instrument
panel, between the steering wheel and

Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
346 VEHICLE CARE
.How far the vehicle will be towed.
Some vehicles have restrictions on
how far and how long they can be
towed.
.The proper towing equipment. See
your dealer or trailering professional
for additional advice and equipment
recommendations.
.If the vehicle is ready to be towed.
Just as preparing the vehicle for a
long trip, make sure the vehicle is
prepared to be towed.
Caution
Use of a shield mounted in front of
the vehicle grille could restrict
airflow and cause damage to the
transmission. The repairs would not
be covered by the vehicle warranty.
If using a shield, only use one that
attaches to the towing vehicle.
Dinghy Towing
Caution
If the vehicle is towed with all four
wheels on the ground, the
drivetrain components could be
damaged. The repairs would not be
covered by the vehicle warranty. Do
not tow the vehicle with all four
wheels on the ground.
The vehicle is neither designed nor
intended to be towed with all four
wheels on the ground. If the vehicle
must be towed, a dolly should be
used. See the following information on
dolly towing.
Dolly Towing
Loading up to the Dolly 1. On level ground start the engine.
2. Release the park brake.
3. Apply the brake pedal and hold until the end of step 5.
4. Push and hold the Electric Parking Brake (EPB) switch. After
15 seconds, the EPB amber telltale
will begin flashing in the IP cluster.
5. When the indicator flashes amber, release the EPB within five seconds.
Then, push and release the EPB
switch and release the brake pedal.