2021 CADILLAC CT4 maintenance

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
196 CLIMATE CONTROLS
Climate Controls
Climate Control Systems
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Climate Control Systems
Dual Automatic Climate Control System
The climate control buttons on the center stack and on the climate control
display are used to adjust the heating, cooling, and ventilation system. Center
Stack Climate Controls
1. ON/OFF (Power)
2. AUTO (Automatic Operation)
3. Air Delivery Mode Control
4. Driver Temperature Controls
5. Fan Control
6. Passenger Temperature Controls7. A/C (Air Conditioning)
8. Recirculation
9. SYNC (Synchronized Temperature)
10. Defrost
11. Rear Window Defogger

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
CLIMATE CONTROLS 201
Move the slider knobs to change the
direction of or to close off the airf low.
Operation Tips
.Clear away any ice, snow, or leaves
from air inlets at the base of the
windshield that could block the
flow of air into the vehicle.
.Clear snow off the hood to improve
visibility and help decrease moisture
drawn into the vehicle.
.Keep the path under the front seats
clear of objects to help circulate the
air inside of the vehicle more
effectively.
.Use of non-GM approved hood
deflectors can adversely affect the
performance of the system. Check
with your dealer before adding
equipment to the outside of the
vehicle.
.Do not attach any devices to the air
vent slats. This restricts airf low and
may cause damage to the air vents.
Maintenance
Passenger Compartment
Air Filter
The filter reduces dust, pollen, and
other airborne irritants from outside
air that is pulled into the vehicle. The
filter should be replaced as part of
routine scheduled maintenance. See
Maintenance Schedule0380.
See your dealer regarding replacement
of the filter.
Service
All vehicles have a label underhood
that identifies the refrigerant used in
the vehicle. The refrigerant system
should only be serviced by trained and
certified technicians. The air
conditioning evaporator should never
be repaired or replaced by one from a
salvage vehicle. It should only be
replaced by a new evaporator to
ensure proper and safe operation. During service, all refrigerants should
be reclaimed with proper equipment.
Venting refrigerants directly to the
atmosphere is harmful to the
environment and may also create
unsafe conditions based on inhalation,
combustion, frostbite, or other
health-based concerns.
The air conditioning system requires
periodic maintenance. See
Maintenance Schedule
0380.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 203
Automatic EmergencyBraking (AEB) . . . . . . . . . . . . . . . . . . . 285
Front Pedestrian Braking (FPB) System . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Side Blind Zone Alert (SBZA) . . . . 289
Lane Change Alert (LCA) . . . . . . . . 289
Lane Keep Assist (LKA) . . . . . . . . . . 291
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . 293
Recommended Fuel (LSY 2.0L L4
Turbo Engine) . . . . . . . . . . . . . . . . . . . 293
Recommended Fuel (L3B 2.7L L4 Turbo Engine) . . . . . . . . . . . . . . . . . . . 294
Prohibited Fuels . . . . . . . . . . . . . . . . . . 294
Fuels in Foreign Countries . . . . . . . 294
Fuel Additives . . . . . . . . . . . . . . . . . . . . 294
Filling the Tank . . . . . . . . . . . . . . . . . . 295
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . . . . . . 296
Trailer Towing
General Towing Information . . . . 297
Driving Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . 297
Trailer Towing (LSY 2.0L L4 Engine) . . . . . . . . . . . . . . . . . . . . . . . . . . 300
Towing Equipment . . . . . . . . . . . . . . . 302
Conversions and Add-Ons
Add-On Electrical Equipment . . . 303
Driving Information
Driving for Better Fuel
Economy
Driving habits can affect fuel mileage.
Here are some driving tips to get the
best fuel economy possible:
.Set the climate controls to the
desired temperature after the engine
is started, or turn them off when
not required.
.Avoid fast starts and accelerate
smoothly.
.Brake gradually and avoid abrupt
stops.
.Avoid idling the engine for long
periods of time.
.When road and weather conditions
are appropriate, use cruise control.
.Always follow posted speed limits or
drive more slowly when conditions
require.
.Keep vehicle tires properly inflated.
.Combine several trips into a
single trip.
.Replace the vehicle's tires with the
same TPC Spec number molded into
the tire's sidewall near the size.
.Follow recommended scheduled
maintenance.
Distracted Driving
Distraction comes in many forms and
can take your focus from the task of
driving. Exercise good judgment and
do not let other activities divert your
attention away from the road. Many
local governments have enacted laws
regarding driver distraction. Become
familiar with the local laws in
your area.
To avoid distracted driving, keep your
eyes on the road, keep your hands on
the steering wheel, and focus your
attention on driving.
.Do not use a phone in demanding
driving situations. Use a hands-free
method to place or receive
necessary phone calls.
.Watch the road. Do not read, take
notes, or look up information on
phones or other electronic devices.
.Designate a front seat passenger to
handle potential distractions.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 205
(60 mph) travels 20 m (66 ft), which
could be a lot of distance in an
emergency.
Helpful braking tips to keep in mind
include:
.Keep enough distance between you
and the vehicle in front of you.
.Avoid needless heavy braking.
.Keep pace with traffic.
If the engine ever stops or a brake
fault occurs, the brakes may lose
power assist. More effort will be
required to stop the vehicle and it can
take longer to stop.
Steering
Caution
To avoid damage to the steering
system, do not drive over curbs,
parking barriers, or similar objects
at speeds greater than 3 km/h
(1 mph). Use care when driving over
other objects such as lane dividers
and speed bumps. Damage caused
by misuse of the vehicle is not
covered by the vehicle warranty.
Electric Power Steering
The vehicle has electric power
steering. It does not have power
steering fluid. Regular maintenance is
not required.
If power steering assist is lost due to a
system malfunction, the vehicle can
be steered, but may require increased
effort.
If the steering assist is used for an
extended period of time while the
vehicle is not moving, power assist
may be reduced. If the steering wheel is turned until it
reaches the end of its travel and is
held against that position for an
extended period of time, power
steering assist may be reduced.
Normal use of the power steering
assist should return when the system
cools down.
See your dealer if there is a problem.
Curve Tips
.Take curves at a reasonable speed.
.Reduce speed before entering a
curve.
.Maintain a reasonable steady speed
through the curve.
.Wait until the vehicle is out of the
curve before accelerating gently into
the straightaway.
Steering in Emergencies
.There are some situations when
steering around a problem may be
more effective than braking.
.Holding both sides of the steering
wheel allows you to turn
180 degrees without removing
a hand.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
248 DRIVING AND OPERATING
Automatic Transmissions
.The brake pedal is firmly pressed to
the floor, equivalent to a panic
brake event.
.The accelerator pedal is rapidly
applied to wide open throttle. If the
vehicle rolls due to wide open
throttle, release the throttle, press
the brake pedal more firmly, and
re-apply the accelerator to wide
open throttle.
Launch Control will initially limit
engine speed as you rapidly apply the
accelerator pedal to wide open
throttle. Allow the engine rpm to
stabilize. A smooth, quick release of
the brake pedal, while maintaining the
fully pressed accelerator pedal, will
manage wheel slip.
After the vehicle is launched, the
system continues in Competitive
Driving Mode or PTM.
Competitive Driving Mode, PTM, and
Launch Control are systems designed
for a closed course race track and not
intended for public roads. The systems are not intended to compensate for
lack of driver experience or familiarity
with the race track.Limited-Slip Differential
If equipped, the Electronic
Limited-Slip Differential (eLSD) is
automatically activated. eLSD actively
monitors vehicle sensors and driver
inputs to determine the amount of
change for the conditions. With eLSD,
the vehicle has:
.Enhanced high-speed control.
.Improved traction through corners,
allowing more acceleration.
.More precise steering.
.Increased vehicle agility.
.Integration with StabiliTrak/
Electronic Stability Control (ESC).
For vehicles with eLSD, driven under
severe conditions, the rear axle fluid
should be changed. See Competitive
Driving Mode 0246 and
Maintenance Schedule 0380.
Cruise Control
{
Warning
Cruise control can be dangerous
where you cannot drive safely at a
steady speed. Do not use cruise
control on winding roads or in
heavy traffic.
Cruise control can be dangerous on
slippery roads. On such roads, fast
changes in tire traction can cause
excessive wheel slip, and you could
lose control. Do not use cruise
control on slippery roads.
With cruise control, a speed of about
40 km/h (25 mph) or more can be
maintained without keeping your foot
on the accelerator. Cruise control does
not work at speeds below about
40 km/h (25 mph).
If the Traction Control/StabiliTrak/
Electronic Stability Control (ESC)
system begins to limit wheel spin
while using cruise control, the cruise
control automatically disengages. See
Traction Control/Electronic Stability
Control 0239. If a collision alert

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
300 DRIVING AND OPERATING
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off immediately
after towing at high altitude on steep
uphill grades, the vehicle could show
signs similar to engine overheating. To
avoid this, let the engine run,
preferably on level ground, with the
transmission in P (Park) for a few
minutes before turning the engine off.
If the overheat warning comes on, see
Engine Overheating0322.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and trailer
on a level surface when possible.
When parking your vehicle and your
trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the
wheels into the curb if facing
downhill or into traffic if facing
uphill. 2. Have someone place chocks under
the trailer wheels.
3. When the wheel chocks are in place, gradually release the brake
pedal to allow the chocks to absorb
the load of the trailer.
4. Reapply the brake pedal. Then apply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into a gear.
.Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more often
when used to tow trailers. See
Maintenance Schedule 0380. It is
especially important to check the automatic transmission fluid, engine
oil, axle lubricant, belts, cooling
system, and brake system before and
during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling when Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See
Engine Overheating
0 322.
Trailer Towing (LSY 2.0L L4
Engine)
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer for
important information about
towing a trailer with the vehicle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 303
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.
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.
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) 097.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
(Continued)
Warning (Continued)
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
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 057 and
Adding Equipment to the
Airbag-Equipped Vehicle 058.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 307
This vehicle has an airbag system.
Before attempting to do your own
service work, seeServicing the
Airbag-Equipped Vehicle 057.
If equipped with remote vehicle start,
open the hood before performing any
service work to prevent remote
starting the vehicle accidentally. See
Remote Vehicle Start 013.
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records 0394.
Caution
Even small amounts of
contamination can cause damage to
vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto engine stop/
start, turn the vehicle off before
opening the hood. If the vehicle is
on, the engine will start when the
hood is opened. You or others could
be injured.
{Warning
Components under the hood can
get hot from running the engine. To
help avoid the risk of burning
unprotected skin, never touch these
components until they have cooled,
and always use a glove or towel to
avoid direct skin contact.
Clear any snow from the hood before
opening. To open the hood:1. Pull the hood release lever with the
isymbol. It is on the lower left
side of the instrument panel.