warning light CADILLAC CT4 2021 Owner's Guide

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 95
Metric
This gauge measures the temperature
of the vehicle's engine.
While driving under normal operating
conditions, if the red LED is
illuminated, the engine is too hot. Pull
off the road, stop the vehicle, and turn
off the engine as soon as possible.
Engine Coolant
Temperature Gauge
(Uplevel)
This gauge shows the engine coolant
temperature.
If the gauge pointer moves into the
red zone, the engine is too hot.
This reading indicates the same thing
as the warning light. It means that the
engine coolant has overheated. If the
vehicle has been operating under
normal driving conditions, pull off the
road, stop the vehicle, and turn off the
engine as soon as possible. See Engine
Overheating 0322 for more
information.
Seat Belt Reminders
Driver Seat Belt Reminder Light
There is a driver seat belt reminder
light on the instrument cluster.
When the vehicle is started, this light
flashes and a chime may come on to
remind the driver to fasten their
seat belt.
Then the light stays on solid until the
belt is buckled. This cycle may
continue several times if the driver
remains or becomes unbuckled while
the vehicle is moving.
If the driver seat belt is buckled,
neither the light nor the chime
comes on.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
96 INSTRUMENTS AND CONTROLS
Front Passenger Seat Belt
Reminder Light
The vehicle may have a front
passenger seat belt reminder light
near the passenger airbag status
indicator. SeePassenger Sensing
System 053.
When the vehicle is started, this light
flashes and a chime may come on to
remind passengers to fasten their
seat belt.
Then the light stays on solid until the
belt is buckled. This cycle continues
several times if the front passenger
remains or becomes unbuckled while
the vehicle is moving.
If the front passenger seat belt is
buckled, neither the chime nor the
light comes on. The front passenger seat belt reminder
light and chime may come on if an
object is put on the seat such as a
briefcase, handbag, grocery bag,
laptop, or other electronic device. To
turn off the reminder light and/or
chime, remove the object from the
seat or buckle the seat belt.
Airbag Readiness Light
This light shows if there is an
electrical problem with the airbag
system. The system check includes
the airbag sensor(s), the passenger
sensing system, the pretensioners, the
airbag modules, the wiring, and the
crash sensing and diagnostic module.
For more information on the airbag
system, see
Airbag System 048.
The airbag readiness light comes on
for several seconds when the vehicle is
started. If the light does not come on
then, have it fixed immediately.
{Warning
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in the
vehicle might not inflate in a crash,
or they could even inflate without a
crash. To help avoid injury, have
the vehicle serviced right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
Passenger Airbag Status
Indicator
The vehicle has a passenger sensing
system. See Passenger Sensing System
0 53 for important safety information.
The overhead console has a passenger
airbag status indicator.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 97
When the vehicle is started, the
passenger airbag status indicator will
light ON and OFF, and the symbols for
on and off, for several seconds as a
system check. Then, after several more
seconds, the status indicator will light
either ON or OFF, and either the
symbol for on or off, to let you know
the status of the front outboard
passenger frontal airbag and knee
airbag.
If the word ON, and the on symbol, is
lit on the passenger airbag status
indicator, it means that the front
outboard passenger frontal airbag and
knee airbag are allowed to inflate.
If the word OFF, and the off symbol, is
lit on the passenger airbag status
indicator, it means that the passenger
sensing system has turned off the
front outboard passenger frontal
airbag and knee airbag.If, after several seconds, all of the
symbols remain lit, or if no symbols
are lit, or if the airbag readiness light
is on, there may be a problem with
the lights or the passenger sensing
system. See your dealer for service
right away.
{Warning
If the airbag readiness light ever
comes on and stays on, it means
that something may be wrong with
the airbag system. To help avoid
injury to yourself or others, have
the vehicle serviced right away. See
Airbag Readiness Light
096 for more
information, including important
safety information.
Charging System Light
The charging system light comes on
briefly when the ignition is turned on,
but the engine is not running, as a
check to show the light is working.
It should go out when the engine is
started.
If the light stays on, or comes on
while driving, there may be a problem
with the electrical charging system.
Have it checked by your dealer.
Driving while this light is on could
drain the battery.
When this light comes on, or is
flashing, the Driver Information
Center (DIC) also displays a message.
If a short distance must be driven
with the light on, be sure to turn off
all accessories, such as the radio and
air conditioner. Find a safe place to
stop the vehicle.
Malfunction Indicator Lamp
(Check Engine Light)
This light is part of the vehicle’s
emission control on-board diagnostic
system. If this light is on while the
engine is running, a malfunction has
been detected and the vehicle may

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 99
.Poor fuel quality can cause
inefficient engine operation and
poor driveability, which may go
away once the engine is warmed up.
If this occurs, change the fuel
brand. It may require at least one
full tank of the proper fuel to turn
the light off. SeeRecommended Fuel
(LSY 2.0L L4 Turbo Engine) 0293 or
Recommended Fuel (L3B 2.7L L4
Turbo Engine) 0294.
If the light remains on, see your
dealer.
Emissions Inspection and
Maintenance Programs
If the vehicle requires an Emissions
Inspection/Maintenance test, the test
equipment will likely connect to the
vehicle's Data Link Connector (DLC).
The DLC is under the instrument
panel to the left of the steering wheel.
Connecting devices that are not used
to perform an Emissions Inspection/
Maintenance test or to service the
vehicle may affect vehicle operation.
See Add-On Electrical Equipment 0303.
See your dealer if assistance is needed.
The vehicle may not pass
inspection if:
.The light is on when the engine is
running.
.The light does not come on when
the ignition is in Service Mode.
.Critical emission control systems
have not been completely
diagnosed. If this happens, the
vehicle would not be ready for
inspection and might require
several days of routine driving
before the system is ready for
inspection. This can happen if the
12-volt battery has recently been
replaced or run down, or if the
vehicle has been recently serviced.
See your dealer if the vehicle will not
pass or cannot be made ready for
the test.
Brake System Warning
Light
MetricEnglish
This light should come on briefly
when the vehicle is turned on. If it
does not come on then, have it fixed
so it will be ready to warn you if there
is a problem.
If the light comes on and stays on at
start up, there is a brake problem.
Have the brake system inspected
right away.
If the light comes on while driving,
pull off the road and stop carefully.
The brake system has electric brake
boost. Vehicle speed may be limited
when the brake system warning light
comes on. The brake pedal might be
harder to push, or the brake pedal
may go closer to the floor. It could

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
100 INSTRUMENTS AND CONTROLS
take longer to stop. If the light is still
on, have the vehicle towed for service.
SeeTowing the Vehicle 0369.
{Warning
The brake system might not be
working properly if the brake
system warning light is on. Driving
with the brake system warning light
on can lead to a crash. If the light is
still on after the vehicle has been
pulled off the road and carefully
stopped, have the vehicle towed for
service.
Electric Parking Brake
Light
MetricEnglish
This light comes on when the parking
brake is applied. If the light continues
flashing after the parking brake is
released, or while driving, there is a problem with the Electric Parking
Brake system. A message may also
display in the Driver Information
Center (DIC).
If the light does not come on,
or remains flashing, see your dealer.
Service Electric Parking
Brake Light
On some vehicles the service electric
parking brake light should come on
briefly when the vehicle is started.
If it does not come on, have it fixed so
it will be ready to warn if there is a
problem. For vehicles with the
reconfigurable cluster, this light may
not come on when the vehicle is
started.
If this light stays on, the vehicle
should be taken to a dealer as soon as
possible. See
Electric Parking Brake
0 237. A message may also display in
the Driver Information Center (DIC).
Antilock Brake System
(ABS) Warning Light
This warning light should come on
briefly when the vehicle is turned on.
If the light does not come on, have it
fixed so it will be ready to warn if
there is a problem.
If the light comes on while driving,
safely stop as soon as it is possible
and turn off the vehicle. Then turn on
the vehicle again to reset the system.
If the ABS warning light stays on,
or comes on again while driving, the
vehicle needs service. A chime may
also sound when the light stays on.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 101
If the ABS warning light is the only
light on, the vehicle has regular
brakes, but ABS is not functioning.
If both the ABS warning light and the
brake system warning light are on,
ABS is not functioning and there is a
problem with the regular brakes. See
your dealer for service.
SeeBrake System Warning Light 099.
Performance Shifting Light
If equipped, this light may display
green when Sport Mode is activated
and certain driving conditions are
met. Sport Mode detects when the
vehicle is being driven in a
competitive manner, and adjusts the
shifting of the gears accordingly. See
Driver Mode Control 0241.
Automatic Vehicle Hold
(AVH) Light
This light comes on when AVH is
turned on. See Automatic Vehicle Hold
(AVH) 0239.
Lane Keep Assist (LKA)
Light
After the vehicle is started, this light
turns off and stays off if LKA has not
been turned on or is unavailable.
If equipped, this light is white if LKA
is turned on, but not ready to assist.
This light is green if LKA is turned on
and is ready to assist. LKA may assist by gently turning the
steering wheel if the vehicle
approaches a detected lane marking.
The LKA light is amber when
assisting.
This light flashes amber as a Lane
Departure Warning (LDW) alert, to
indicate that the lane marking has
been crossed.
LKA will not assist or alert if the turn
signal is active in the direction of lane
departure, or if LKA detects that you
are accelerating, braking, or actively
steering.
See
Lane Keep Assist (LKA) 0291.
Automatic Emergency
Braking (AEB) Disabled
Light

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 103
If StabiliTrak/ESC is off, the Traction
Control System (TCS) is also off. To
turn ESC off and on, seeTraction
Control/Electronic Stability Control
0 239.
If ESC and TCS are off, the systems do
not assist in controlling the vehicle.
Adjust driving accordingly.
Traction Control System
(TCS)/StabiliTrak Light
This light comes on briefly when the
vehicle is turned on.
If the light does not come on, have
the vehicle serviced by your dealer.
If the system is working normally, the
indicator light turns off.
If the light is on and not flashing, the
TCS and potentially the StabiliTrak/
ESC system are not fully operational
and may not assist in maintaining
control. Adjust driving accordingly. If the condition persists, see your
dealer as soon as possible. A Driver
Information Center (DIC) message
may display.
The light flashes when the TCS and/or
the StabiliTrak/ESC system is actively
working.
See
Traction Control/Electronic Stability
Control 0239.
Engine Coolant
Temperature Warning Light
On some vehicles this light comes on
briefly while starting the vehicle. If it
does not, have the vehicle serviced by
the dealer. If the system is working
normally the indicator light goes off.
For vehicles with the reconfigurable
cluster, this light may not come on
when starting the vehicle.
Caution
The engine coolant temperature
warning light indicates that the
vehicle has overheated. Driving with
this light on can damage the engine
and it may not be covered by the
vehicle warranty. See Engine
Overheating 0322.
The engine coolant temperature
warning light comes on when the
engine has overheated.
If this happens pull over and turn off
the engine as soon as possible. See
Engine Overheating 0322.
Driver Mode Control Light
This light comes on when Sport Mode
is selected.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 105
This light should come on briefly as
the engine is started. If it does not
come on, have the vehicle serviced by
your dealer.
If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle could
be low on oil and might have some
other system problem. See your dealer.
Low Fuel Warning Light
A Low Fuel Warning Light near the
fuel gauge comes on briefly when the
ignition is turned on as a check to
show it is working.It also comes on when the fuel gauge
indicator nears empty. The light turns
off when fuel is added. If it does not,
have the vehicle serviced.
Security Light
The security light should come on
briefly as the engine is started. If it
does not come on, have the vehicle
serviced by your dealer. If the system
is working normally, the indicator
light turns off.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system. See
Immobilizer Operation
0 23.
High-Beam On Light
This light comes on when the
high-beam headlamps are in use. See
Headlamp High/Low-Beam Changer
0128.
IntelliBeam Light
This light comes on when the
IntelliBeam system, if equipped, is
enabled. See Exterior Lamp Controls
0 126.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
114 INSTRUMENTS AND CONTROLS
The HUD image will automatically
dim and brighten to compensate for
outside lighting. The HUD brightness
control can also be adjusted as
needed.
The HUD image can temporarily light
up depending on the angle and
position of sunlight on the HUD
display. This is normal.
Polarized sunglasses could make the
HUD image harder to see.
Head-Up Display (HUD) Rotation
Option
This feature allows for adjusting the
angle of the HUD image.
Press the thumbwheel on the steering
wheel controls while Head-Up Display
Rotation is highlighted to enter Main
View. From Main View, press the
thumbwheel to enter the Adjust
Menu. Press
yorzto adjust the
angle of the HUD display. Press
Sor
Tto highlight OK, then press the
thumbwheel to save the setting.
CANCEL can also be selected to cancel
the setting. The vehicle must be in P (Park). See
Instrument Cluster (Base
Level) 088 or
Instrument Cluster (Uplevel) 090.
HUD Views
There are three views in the HUD.
Track mode is available for V-Series
only. Some vehicle information and
vehicle messages or alerts may be
displayed in any view.
Metric
English
Speed View : This displays digital
speed in English or metric units,
speed limit, vehicle ahead indicator,
Lane Departure Warning/Lane Keep Assist, and Adaptive Cruise Control
and set speed. Some information only
appears on vehicles that have these
features, and when they are active.
Metric
English
Performance View : This displays
digital speed, indicators from speed
view along with rpm reading, vehicle
ahead indicator, Lane Departure
Warning/Lane Keep Assist, and
Adaptive Cruise Control and set speed.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
126 LIGHTING
Lighting
Exterior Lighting
Exterior Lamp Controls . . . . . . . . . . 126
Exterior Lamps Off Reminder . . . 128
Headlamp High/Low-BeamChanger . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . 128
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . . . 128
Automatic Headlamp System . . . 128
Hazard Warning Flashers . . . . . . . . 129
Turn and Lane-Change Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Cornering Lamps . . . . . . . . . . . . . . . . . 130
Interior Lighting
Instrument Panel Illumination Control . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Courtesy Lamps . . . . . . . . . . . . . . . . . . 130
Dome Lamps . . . . . . . . . . . . . . . . . . . . . 130
Reading Lamps . . . . . . . . . . . . . . . . . . . 131
Lighting Features
Entry Lighting . . . . . . . . . . . . . . . . . . . . 131
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . 132
Battery Load Management . . . . . . 132
Battery Power Protection . . . . . . . . 133
Exterior Lighting Battery Saver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Exterior Lighting
Exterior Lamp Controls
The exterior lamp control is on the
turn signal lever.
Turn the control to the following
positions:
O:Turns the exterior lamps off and
deactivates the AUTO mode. Turn to
Oagain to reactivate the AUTO mode.
In Canada, the headlamps will
automatically reactivate when the
vehicle is shifted out of P (Park).
AUTO : Automatically turns the
exterior lamps on and off, depending
on outside lighting.
;: Turns on the parking lamps
including all lamps, except the
headlamps.
2: Turns on the headlamps together
with the parking lamps and
instrument panel lights.
IntelliBeam System
If equipped, this system turns the
vehicle's high-beam headlamps on and
off according to surrounding traffic
conditions.
The system turns the high-beam
headlamps on when it is dark enough
and there is no other traffic present.
This light
bcomes on in the
instrument cluster when the
IntelliBeam system is enabled.