light CADILLAC CT4 2020 Owners Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 233
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 234
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 234
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 235
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 235
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 235
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 238
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 241
Engine Oil Life System . . . . . . . . . . . 243
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Engine Air Cleaner/Filter . . . . . . . . . 245
Cooling System . . . . . . . . . . . . . . . . . . . 246
Engine Overheating . . . . . . . . . . . . . . 250
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 252
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 253
Battery - North America . . . . . . . . . 254
All-Wheel Drive . . . . . . . . . . . . . . . . . . 255 Starter Switch Check . . . . . . . . . . . . . 255
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 256
Wiper Blade Replacement . . . . . . . 256
Windshield Replacement . . . . . . . . 257
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 257
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 258
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 258
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . 258
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 259
LED Lighting . . . . . . . . . . . . . . . . . . . . . 259
Front Turn Signal Lamps . . . . . . . . 259
Electrical System
Electrical System Overload . . . . . . 259
Fuses and Circuit Breakers . . . . . . 260
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Instrument Panel Fuse Block . . . . 262
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
All-Season Tires . . . . . . . . . . . . . . . . . . 268
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 268
Run-Flat Tires . . . . . . . . . . . . . . . . . . . . 269 Self-Sealing Tires . . . . . . . . . . . . . . . . . 269
Low-Profile Tires . . . . . . . . . . . . . . . . . 270
Summer Tires . . . . . . . . . . . . . . . . . . . . 270
Tire Sidewall Labeling . . . . . . . . . . . 270
Tire Designations . . . . . . . . . . . . . . . . . 272
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 272
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 275
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 276
Tire Pressure Monitor System . . . 276
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 277
Tire Inspection . . . . . . . . . . . . . . . . . . . 280
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 281
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Buying New Tires . . . . . . . . . . . . . . . . 282
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Uniform Tire Quality Grading . . . 284
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Wheel Replacement . . . . . . . . . . . . . . 286
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 286
If a Tire Goes Flat . . . . . . . . . . . . . . . . 287Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 288

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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VEHICLE CARE 253
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
If equipped with high performance
brake linings, there could be an
increased build-up of brake dust as
well as minor noises as compared to
standard brake linings.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications. See Capacities and
Specifications 0318.
Brake pads should be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does
not return to normal height, or if
there is a rapid increase in pedal
travel. This could be a sign that brake
service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement parts.
If this is not done, the brakes may not
work properly. The braking
performance expected can change in
many other ways if the wrong
replacement brake parts are installed
or parts are improperly installed.
Brake Fluid
The brake master cylinder reservoir is
filled with GM approved DOT 3 brake
fluid as indicated on the reservoir cap.
See Engine Compartment Overview
0 238 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

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254 VEHICLE CARE
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 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
0 102.
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 0303. What to Add
Use only GM approved DOT 3 brake
fluid from a clean, sealed container.
See
Recommended Fluids and
Lubricants 0313.{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the paint
finish can be damaged. Immediately
wash off any painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the
cap and do not add fluid. Refer to the replacement number
shown on the original battery label
when a new battery is needed.
The vehicle has an Absorbed Glass
Mat (AGM) 12-volt battery.
Installation of a standard 12-volt
battery will result in reduced 12-volt
battery life.
When using a 12-volt battery charger
on the 12-volt AGM battery, some
chargers have an AGM battery setting
on the charger. If available, use the
AGM setting on the charger, to limit
charge voltage to 14.8 volts. Follow
the charger manufacturer's
instructions.
Stop/Start System
This vehicle has a Stop/Start system
to shut off the engine to help
conserve fuel. See
Stop/Start System
0 161.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 259
High Intensity Discharge
(HID) Lighting
{Warning
The High Intensity Discharge (HID)
lighting system operates at a very
high voltage. If you try to service
any of the system components, you
could be seriously injured. Have
your dealer or a qualified technician
service them.
After an HID headlamp bulb has been
replaced, the beam might be a slightly
different shade than it was originally.
This is normal.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.
Front Turn Signal Lamps
Uplevel
See your dealer for turn signal
replacement.
Base level
To replace one of these lamps: 1. Open the hood.
2. Turn the bulb socket counterclockwise to remove it
from the headlamp assembly.
3. Unplug the electrical connector from the bulb by releasing the
clip on the connector.
4. Replace the bulb and reverse Steps 1–3 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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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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) -
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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) -
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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) -
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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.

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VEHICLE CARE 273
Bias Ply Tire:A pneumatic tire in
which the plies are laid at
alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
:The amount
of air pressure in a tire, measured
in kPa (kilopascal) or psi (pounds
per square inch) before a tire has
built up heat from driving. See
Tire Pressure 0275.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil, and
coolant, but without passengers
and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code includes
the Tire Identification Number
(TIN), an alphanumeric designator which can also identify the tire
manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 154.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0154.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits 0154.
Intended Outboard Sidewall
:
The side of an asymmetrical tire
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric unit
for air pressure.
Light Truck (LT-Metric) Tire
:A
tire used on light duty trucks and
some multipurpose passenger
vehicles. Load Index
:An assigned number
ranging from 1 to 279 that
corresponds to the load carrying
capacity of a tire.
Maximum Inf lation Pressure
:
The maximum air pressure to
which a cold tire can be inflated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The load
rating for a tire at the maximum
permissible inflation pressure for
that tire.
Maximum Loaded Vehicle
Weight
:The sum of curb weight,
accessory weight, vehicle capacity
weight, and production options
weight.
Normal Occupant Weight
:The
number of occupants a vehicle is
designed to seat multiplied by
68 kg (150 lb). See Vehicle Load
Limits 0154.
Occupant Distribution
:
Designated seating positions.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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274 VEHICLE CARE
Outward Facing Sidewall:The
side of an asymmetrical tire that
has a particular side that faces
outward when mounted on a
vehicle. The side of the tire that
contains a whitewall, bears white
lettering, or bears manufacturer,
brand, and/or model name
molding that is higher or deeper
than the same moldings on the
other sidewall of the tire.
Passenger (P-Metric) Tire
:A tire
used on passenger cars and some
light duty trucks and
multipurpose vehicles.
Recommended Inf lation
Pressure
:Vehicle manufacturer's
recommended tire inflation
pressure as shown on the tire
placard. See Tire Pressure 0275
and
Vehicle Load Limits 0154.
Radial Ply Tire
:A pneumatic tire
in which the ply cords that extend
to the beads are laid at 90 degrees
to the centerline of the tread. Rim
:A metal support for a tire
and upon which the tire beads are
seated.
Sidewall
:The portion of a tire
between the tread and the bead.
Speed Rating
:An alphanumeric
code assigned to a tire indicating
the maximum speed at which a
tire can operate.
Traction
:The friction between
the tire and the road surface. The
amount of grip provided.
Tread
:The portion of a tire that
comes into contact with the road.
Treadwear Indicators
:Narrow
bands, sometimes called wear
bars, that show across the tread of
a tire when only 1.6 mm (1/16 in)
of tread remains. See When It Is
Time for New Tires 0282.
UTQGS (Uniform Tire Quality
Grading Standards)
:A tire
information system that provides
consumers with ratings for a tire's
traction, temperature, and treadwear. Ratings are determined
by tire manufacturers using
government testing procedures.
The ratings are molded into the
sidewall of the tire. See
Uniform
Tire Quality Grading 0284.
Vehicle Capacity Weight
:The
number of designated seating
positions multiplied by
68 kg (150 lb) plus the rated cargo
load. See Vehicle Load Limits 0154.
Vehicle Maximum Load on the
Tire
:Load on an individual tire
due to curb weight, accessory
weight, occupant weight, and
cargo weight.
Vehicle Placard
:A label
permanently attached to a vehicle
showing the vehicle capacity
weight and the original equipment
tire size and recommended
inflation pressure. See “Tire and
Loading Information Label” under
Vehicle Load Limits 0154.