CADILLAC CT4 2020 Owner's Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
260 VEHICLE CARE
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.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop. Wiper function is
available immediately after the wiper
switch is set to off, and back to on.
To protect the wiper motor from
overheating, the wipers may slow
down when the windshield is dry for a
long period of time. If a period of dry
operation, or little moisture, exceeds
10 minutes, the wipers may switch to
intermittent operation, and remain
there. When moisture is again
detected on the windshield, wiper
operation will return to the operator
selected speed.
Although the circuit is protected from
electrical overload, overload due to
heavy snow or ice may cause wiperlinkage 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
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.
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 engine compartment fuse block is
on the passenger side of the engine
compartment.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 261
Lift the fuse block cover to access the
fuses.
The vehicle may not be equipped with
all of the fuses and relays shown.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.
FusesUsage
1 Long range radar front sensor
2 Park/Daytime running lamps
3 Exterior lighting module 4
4 Exterior lighting module 7 Fuses
Usage
5 Headlamp level
6 –
7 Electronic brake control module
8 Washer pump
9 –
10 –
11 –

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
262 VEHICLE CARE
FusesUsage
12 Horn
13 Front wiper
14 Exterior lighting module 6
15 Exterior lighting module 1
16 Exterior lighting module 5
17 Exterior lighting module 3
18 Aero shutter
19 –
20 –
21 Virtual key system/ Power sounder
module
22 –
23 Transmission control module
24 Active engine mount
25 – Fuses
Usage
26 Engine control module
27 Injectors/Ignition 2
28 Charged air cooler
29 Transmission coolant pump
30 Injectors/Ignition 1
31 Emissions 1
32 Emissions 2
33 Starter solenoid
34 –
35 Coolant pump
36 Starter pinion
37 AC clutch
38 –
39 –
40 –
41 –
42 Water pump
43 – Fuses
Usage
44 –
Relays Usage
47 –
48 Front wiper speed
49 Front wiper control
51 –
52 Engine control module
53 Starter solenoid
54 Starter pinion
55 –
57 AC clutch
58 –
Instrument Panel Fuse
Block
The instrument panel fuse block is in
the end of the driver side of the
instrument panel.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 263
To access the fuses, remove the end
panel by gently prying with a plastic
tool near each clip, beginning at the
point shown.
To install the end cover, insert the
tabs on the back of the cover into the
slots in the instrument panel at the
points shown. Align the clips with the
slots in the instrument panel, and
press the cover into place.
The vehicle may not be equipped with
all of the fuses and relays shown.
FusesUsage
1 –

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
264 VEHICLE CARE
FusesUsage
2 HVAC blower
3 –
4 –
5 Theft deterrent/ Universal garage door
opener
6 –
7 Air quality ionizer
8 Heated steering wheel
9 –
10 Electronic steering column lock 1
11 –
12 –
13 –
14 –
15 –
16 –
17 –
18 Display/ Infotainment/USB Fuses
Usage
19 Airbag/Automatic occupant sensing/
Data link connection/
Wireless charging
module
20 Power steering column module/
Electronic steering
column lock 2
21 –
22 –
23 –
24 –
25 USB
26 –
27 –
28 –
29 –
30 –
31 Headlamp level
32 – Fuses
Usage
33 Body ignition/IP ignition
34 Exhaust valve
35 Transmission control module ignition/
Engine control
module ignition/Shift
ignition/Brake
ignition
36 Shift module
37 Body control module 1/Electronic
park brake switch
38 Center stack module
39 Steering wheel controls
40 Body control module 2
41 Body control module 3
42 Body control module 4

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 265
Circuit
Breakers Usage
CB1 Auxiliary power outlet 1
CB2 Auxiliary power outlet 2
Relays Usage 1 Run after park/ Accessory
2 Run crank
3 –
4 –
5 –Rear Compartment Fuse
Block
The rear compartment fuse block is
behind a cover on the driver side of
the rear compartment.
The vehicle may not be equipped with
all of the fuses, relays, and features
shown.
Fuses Usage
1 Remote function actuator

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
266 VEHICLE CARE
FusesUsage
2 Engine control module
3 Driver heated seat
4 Fuel tank zone module
5 –
6 –
7 –
8 –
9 –
10 Motor seat belt passenger
11 Canister vent solenoid
12 Sunroof
13 –
14 –
15 Passenger heated seat
16 –
17 Electronic suspension control Fuses
Usage
18 –
19 Motor seat belt driver
20 Rear defog
21 DC to DC transformer 2
22 Driver power window door lock switch
23 External object calculating module/
Front camera module
24 Passenger window door lock switch
25 –
26 Trailer
27 Rear drive control module
28 –
29 –
30 –
31 DC to DC transformer 1 Fuses
Usage
32 Transfer case electronic control
33 Central gateway module/Side blind
zone alert
34 Video processing module
35 Hands free closure release
36 Exterior lighting module 2
37 Passenger memory seat module
38 Trailer 2
39 Right front/Right rear window
40 –
41 –
42 Amplifier
43 Park assist module
44 Driver memory seat module
45 OnStar

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) -
2020 - crc - 4/28/20
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.