2021 CADILLAC CT4 service

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 209
Caution (Continued)
performance or race track driving.
SeeRecommended Fluids and
Lubricants 0391.
Brake Fade Warning Assist
The Brake Fade Warning Assist
system monitors the performance of
the brake system. If the system
detects brake fade, or if the brake
fluid is near the boiling point, the
driver will be alerted.
The Brake Fade Warning Assist
system is designed for use with the
factory-installed brake pads or
GM-approved replacement pads. If the
brake pads on the vehicle need to be
replaced, use GM-approved brake
pads. If this is not done, the brake
fade warning system may not function
properly.
Stage 1 : The Driver Information
Center (DIC) displays a “Reduce
Braking to Avoid Overheating”
message and brake pedal effort and
travel is increased. When the message
displays, the driver should decrease
brake pedal pressure. Stage 2 :
The Driver Information
Center (DIC) displays a “Brakes
Overheated Service Now ”message that
the brake fluid temperature is
excessive and is about to boil. The
system increases brake pedal effort
and travel, and will also limit vehicle
speed. The driver should immediately
start a cool down lap if on the track.
If this message displays, take the
vehicle to be serviced at your dealer.
Brake Burnishing
For vehicles equipped with front
Brembo brake systems:
Performance/racing brake pads are
required prior to racing or closed track
driving. Vehicles with option code JE2
have performance brake pads.
New brake pads must be burnished
before racing or other competitive
driving.
These procedures are specific to the
V-Series brake package. This
procedure should not be performed on
other models as damage may result.
Caution
Performing the brake burnish
procedure on a base brake system
can result in brake damage.
Caution
The new vehicle break-in period
should be completed before
performing the brake burnish
procedure, otherwise damage may
occur to the powertrain/engine. See
New Vehicle Break-In 0218.
Caution
Brake fade will occur during this
track burnish procedure and can
cause brake pedal travel and force
to increase. This could extend
stopping distance until the brakes
are fully burnished.
When this procedure is performed as
instructed, it will not damage the
brakes. The brake pads will smoke and
produce an odor. The braking force

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
212 DRIVING AND OPERATING
{Warning
Wet brakes can cause crashes. They
might not work as well in a quick
stop and could cause pulling to one
side. You could lose control of the
vehicle.
After driving through a large puddle
of water or a car/vehicle wash,
lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be very
cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water can
build up under the vehicle's tires so
they actually ride on the water. This
can happen if the road is wet enoughand you are going fast enough. When
the vehicle is hydroplaning, it has
little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping equipment
in good shape.
.Keep the windshield washer fluid
reservoir filled.
.Have good tires with proper tread
depth. See
Tires0339.
.Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving on
flat or rolling terrain. Tips include:
.Keep the vehicle serviced and in
good shape.
.Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.Shift to a lower gear when going
down steep or long hills.
{Warning
Using the brakes to slow the vehicle
on a long downhill slope can cause
brake overheating, can reduce brake
performance, and could result in a
loss of braking. Shift the
transmission to a lower gear to let
the engine assist the brakes on a
steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or
with the ignition off is dangerous.
This can cause overheating of the
brakes and loss of steering assist.
Always have the engine running
and the vehicle in gear.
.Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the center line.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 213
.Be alert on top of hills; something
could be in your lane (e.g., stalled
car, crash).
.Pay attention to special road signs
(e.g., falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving
Driving on Snow or Ice
Snow or ice between the tires and the
road creates less traction or grip, so
drive carefully. Wet ice can occur at
about 0 °C (32 °F) when freezing rain
begins to fall. Avoid driving on wet ice
or in freezing rain until roads can be
treated.
For slippery road driving:
.Accelerate gently. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick.
.Turn on Traction Control. See
Traction Control/Electronic Stability
Control0239.
.Antilock Brake System (ABS)
improves vehicle stability during
hard stops, but the brakes should be
applied sooner than when on dry
pavement. See Antilock Brake System
(ABS) 0236.
See Driver Mode Control 0241.
.Allow greater following distance and
watch for slippery spots. Icy patches
can occur on otherwise clear roads
in shaded areas. The surface of a
curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice.
.Turn off cruise control.
Blizzard Conditions
Stop the vehicle in a safe place and
signal for help. Stay with the vehicle
unless there is help nearby. If possible,
use Roadside Service. See Roadside
Service 0403. To get help and keep
everyone in the vehicle safe:
.Turn on the hazard warning
flashers.
.Tie a red cloth to an outside mirror.
{Warning
Snow can trap engine exhaust
under the vehicle. This may cause
exhaust gases to get inside. Engine
exhaust contains carbon monoxide
(CO), which cannot be seen or
smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in snow:
.Clear snow from the base of the
vehicle, especially any blocking
the exhaust pipe.
.Open a window about 5 cm (2 in)
on the vehicle side that is away
from the wind, to bring in
fresh air.
.Fully open the air outlets on or
under the instrument panel.
.Adjust the climate control
system to circulate the air inside
the vehicle and set the fan speed
to the highest setting. See
“Climate Control Systems.”
For more information about CO, see
Engine Exhaust 0226.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 219
Ignition Positions
The vehicle has an electronic keyless
ignition with pushbutton start.
The remote key must be in the vehicle
for the system to operate. If the
pushbutton start is not working, the
vehicle may be near a strong radio
antenna signal causing interference to
the Keyless Access system. SeeRemote
Keyless Entry (RKE) System Operation
0 7.
To shift out of P (Park), the vehicle
must be on, and the brake pedal must
be applied. Stopping the Engine/OFF (No
Indicator Lights) :
When the vehicle
is stopped, press ENGINE START/
STOP once to turn the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory Power
(RAP) 0223.
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display a message in
the Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
switch to OFF.
The vehicle may have an electric
steering column lock. The lock is
activated when the vehicle is switched
to OFF and the driver door is opened.
A sound may be heard as the lock
actuates or releases. The steering
column lock may not release with the
wheels turned off center. If this
happens, the vehicle may not start.
Move the steering wheel from left to
right while attempting to start the
vehicle. If this does not work, the
vehicle needs service. Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake and
steering systems and disable the
airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steady pressure. Do not pump the brakes
repeatedly. This may deplete power
assist, requiring increased brake
pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the vehicle
is moving. After shifting to
N (Neutral), firmly apply the brakes
and steer the vehicle to a safe
location.
3. Come to a complete stop, shift to P (Park), and turn the ignition to
OFF. On vehicles with an automatic
transmission, the shift lever must
be in P (Park) to turn the ignition
switch to the OFF position.
4. Set the parking brake. See Electric
Parking Brake 0237.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
220 DRIVING AND OPERATING
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the vehicle
off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
press and hold the ENGINE START/
STOP button for longer than
two seconds, or press twice in
five seconds.
ACC/ACCESSORY (Amber Indicator
Light) : This mode allows you to use
some electrical accessories when the
engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after five minutes
to prevent battery rundown. ON/RUN/START (Green Indicator
Light) :
This mode is for driving and
starting. With the ignition off, and the
brake pedal applied, pressing the
button once will place the ignition
system in ON/RUN/START. Once
engine cranking begins, release the
button. Engine cranking will continue
until the engine starts. See Starting the
Engine 0220. The vehicle will then
remain on.
Service Mode
This power mode is available for
service and diagnostics, and to verify
the proper operation of the
malfunction indicator lamp as may be
required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the button for more than
five seconds will place the vehicle in
Service Mode. The instruments and
audio systems will operate as they do
in ON/RUN, but the vehicle will not be
able to be driven. The engine will not
start in Service Mode. Press the
button again to turn the vehicle off.
Starting the Engine
Place the transmission in the
proper gear
Caution
If you add electrical parts or
accessories, you could change the
way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty. See
Add-On Electrical Equipment 0303.
Move the shift lever to P (Park) or
N (Neutral). To restart the vehicle
when it is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
Starting the Vehicle 1. Press the brake pedal, then press ENGINE START/STOP on the
instrument panel.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 225
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
It could overheat and catch fire.
It is dangerous to get out of the
vehicle if the vehicle is not in
P (Park) with the parking brake set.
The vehicle can roll.
Do not leave the vehicle when the
engine is running. If you have left
the engine running, the vehicle can
move suddenly. You or others could
be injured. To be sure the vehicle
will not move, even when you are
on fairly level ground, always set
the parking brake and shift to
P (Park). SeeShifting Into Park
(Mechanical Shifter) 0223 or
Shifting Into Park (Electronic Shifter)
0 224. If you are towing a trailer,
see Driving Characteristics and
Towing Tips 0297. If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the parking
brake is set before you leave it.
If you are towing a trailer and parking
on a hill, see
Driving Characteristics
and Towing Tips 0297.
Shifting out of Park
(Mechanical Shifter)
This vehicle is equipped with an
electronic shift lock release system.
The shift lock release is designed to
prevent movement of the shift lever
out of P (Park), unless the ignition is
on and the brake pedal is applied.
The shift lock release is always
functional except in the case of an
uncharged or low voltage (less than
9 volt) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See Jump Starting - North
America 0366 for more information. To shift out of P (Park):
1. Apply the brake pedal.
2. Release the parking brake. See Electric Parking Brake 0237.
3. Press the shift lever button.
4. Move the shift lever.
If unable to shift out of P (Park): 1. Fully release the shift lever button.
2. While holding down the brake pedal, press the shift lever button
again.
3. Move the shift lever.
If the shift lever will not move from
P (Park), consult your dealer or a
professional towing service.
Shifting out of Park
(Electronic Shifter)
This vehicle is equipped with an
electronic transmission. The shift lock
release button is designed to prevent
inadvertent shifting out of P (Park).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
226 DRIVING AND OPERATING
To shift out of P (Park):1. Ensure the engine is running.
2. Apply the brake pedal.
3. Press and hold the shift lock release button on the shift lever.
4. Move the shift lever to the desired position. For N (Neutral) hold the
lever in the N (Neutral) position
until the N indicator
illuminates red.
5. The P indicator will turn white and the gear indicator will turn red
when the vehicle is no longer in
P (Park).
6. After releasing the shift lever, it will return to the center position.
If the vehicle cannot shift from
P (Park), a Driver Information Center
(DIC) message may be displayed.
Check that the ignition is on, the
engine is running, the brake pedal is
applied, and the shift lock release
button is pressed when you are
attempting to shift out of P (Park).
If all of these are met but the vehicle
will not shift out of P (Park), see your
dealer for service.Parking over Things
That Burn
{Warning
Things that can burn could touch
hot exhaust parts under the vehicle
and ignite. Do not park over papers,
leaves, dry grass, or other things
that can burn.
Extended Parking
It is best not to park with the vehicle
running. If the vehicle is left running,
be sure it will not move and there is
adequate ventilation.
See Shifting Into Park (Mechanical
Shifter) 0223 or
Shifting Into Park (Electronic Shifter)
0 224 and
Engine Exhaust 0226.
If the vehicle is left parked and
running with the remote key outside
the vehicle, it will continue to run for
up to 15 minutes. If the vehicle is left parked and
running with the remote key inside
the vehicle, it will continue to run for
up to 30 minutes.
The vehicle could turn off sooner if it
is parked on a hill, due to lack of
available fuel.
The timer will reset if the vehicle is
taken out of P (Park) while it is
running.Engine Exhaust
{
Warning
Engine exhaust contains carbon
monoxide (CO), which cannot be
seen or smelled. Exposure to CO
can cause unconsciousness and
even death.
Exhaust may enter the vehicle if:
.The vehicle idles in areas with
poor ventilation (parking garages,
tunnels, deep snow that may
block underbody airf low or tail
pipes). (Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 231
To shift in and out of P (Park), see
Shifting Into Park (Mechanical Shifter)
0223 or
Shifting Into Park (Electronic Shifter)
0 224 and
Shifting out of Park (Mechanical Shifter)
0 225 or
Shifting out of Park (Electronic Shifter)
0 225.
Service Shift Lever Message
If the message SERVICE SHIFTER SEE
OWNER’S MANUAL appears in the
Driver Information Center (DIC), the
shift lever needs service. Have the
vehicle serviced as soon as possible.
If the vehicle is automatically shifting
into P (Park), check to see if the
P (Park) button on top of the shift
lever is stuck. To operate the vehicle,
hold the shift lever in the desired gear,
R (Reverse) or D (Drive), until vehicle
speed exceeds 15 km/h (10 mph), then
release the shift lever.
R : Use this gear to back up.
If the vehicle is shifted from either
R (Reverse) to D (Drive), or D (Drive)
or M (Manual Mode) to R (Reverse)
while the speed is too high, the vehicle will shift to N (Neutral).
Reduce the vehicle speed and try the
shift again.
To shift into R (Reverse):
1. Bring the vehicle to a complete stop.
2. Press and hold shift lock release button on the side of the shift
lever.
3. From the center position, move the shift lever forward through the first
detent to the end of travel. R is
illuminated in red.
4. After releasing the shift lever, it will return to the center position.
To shift out of R (Reverse): 1. Bring the vehicle to a complete stop.
2. Shift to the desired gear.
3. After releasing the shift lever, it will return to the center position.
At low vehicle speeds, R (Reverse) can
be used to rock the vehicle back and
forth to get out of snow, ice, or sand
without damaging the transmission.
See If the Vehicle Is Stuck 0214. N :
In this position, the engine does
not connect with the wheels. To
restart the engine when the vehicle is
already moving, use N (Neutral) only.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift into
a drive gear while the engine is
running at high speed.
Caution
Shifting out of P (Park) or
N (Neutral) with the engine running
at high speed may damage the
transmission. The repairs would not
be covered by the vehicle warranty.
Be sure the engine is not running at
high speed when shifting the
vehicle.