2021 CADILLAC CT4 light

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
102 INSTRUMENTS AND CONTROLS
This indicator will display when
Automatic Emergency Braking or
Front Pedestrian Braking has been
turned off or is currently unavailable
due to malfunction.
SeeAutomatic Emergency Braking
(AEB) 0285.
See Front Pedestrian Braking (FPB)
System 0287.
Vehicle Ahead Indicator
If equipped, this indicator will display
green when a vehicle is detected
ahead and amber when you are
following a vehicle ahead much too
closely.
See Forward Collision Alert (FCA)
System 0283.
Pedestrian Ahead Indicator
If equipped, this indicator will display
amber when a nearby pedestrian is
detected in front of the vehicle.
See Front Pedestrian Braking (FPB)
System 0287.
Traction Off Light
This light comes on briefly when the
vehicle is turned on. If it does not,
have the vehicle serviced by your
dealer. If the system is working
normally, the indicator light then
turns off. The traction off light comes on when
the Traction Control System (TCS) has
been turned off. If StabiliTrak/
Electronic Stability Control (ESC) is
turned off, TCS is also turned off. To
turn TCS and ESC off and on, see
Traction Control/Electronic Stability
Control
0239.
If TCS is off, wheel spin is not limited
unless necessary to help protect the
driveline from damage. Adjust driving
accordingly.
StabiliTrak OFF 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
then turns off.
This light comes on when the
StabiliTrak/Electronic Stability Control
(ESC) system is turned off.

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
104 INSTRUMENTS AND CONTROLS
This light comes on when Snow/Ice
Mode is selected.
This light comes on when Track Mode
is selected. SeeDriver Mode Control
0 241.
This light comes on when V Mode is
selected. See Driver Mode Control
0 241.
This light comes on when My Mode is
selected. See Driver Mode Control
0 241.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine is
started. It provides information about
tire pressures and the TPMS.
When the Light Is On Steady
This indicates that one or more of the
tires are significantly underinflated.
A Driver Information Center (DIC) tire
pressure message may also display.
Stop as soon as possible, and inflate the tires to the pressure value shown
on the Tire and Loading Information
label. See
Tire Pressure 0346.
When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light will
come on at every ignition cycle. See
Tire Pressure Monitor Operation 0349.
Engine Oil Pressure Light
Caution
Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check the
oil level as soon as possible. Add oil
if required, but if the oil level is
within the operating range and the
oil pressure is still low, have the
vehicle serviced. Always follow the
maintenance schedule for changing
engine oil.

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
106 INSTRUMENTS AND CONTROLS
Lamps On Reminder
This light comes on when the exterior
lamps are in use, except when only
the Daytime Running Lamps (DRL)
are active. SeeExterior Lamp Controls
0 126.
Cruise Control Light (Base
Level)
The cruise control light is white when
the cruise control is on and ready, and
turns green when the cruise control is
set and active.
See Cruise Control 0248.
Adaptive Cruise Control Light
This light is white when the Adaptive
Cruise Control (ACC, if equipped) is on
and ready, and turns green when the
ACC is set and active.
See Adaptive Cruise Control (Advanced)
0 251.
Cruise Control Light
(Uplevel)
The cruise control light is white when
the cruise control is on and ready, and
turns green when the cruise control is
set and active.
See Cruise Control 0248.
Adaptive Cruise Control Light
This light is white when the Adaptive
Cruise Control (ACC, if equipped) is on
and ready, and turns green when the
ACC is set and active.
Curve Speed Control Light
If equipped, this light may illuminate
green when ACC is actively controlling
the vehicle speed and detects a sharp
curve on the road ahead.
ACC automatically slows the vehicle
down while navigating the curve and
may increase speed out of the curve,
but will not exceed the set speed.