check engine light CADILLAC CT4 2021 Owner's Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
INTRODUCTION 5
1.Air Vents 0200.
2. Exterior Lamp Controls 0126.
Turn Signal Lever. See Turn and
Lane-Change Signals 0129.
3. Tap Shift Controls (If Equipped). See Manual Mode (Electronic Shifter)
0 235 or
Manual Mode (Mechanical Shifter)
0 234.
4. Cruise Control 0248.
Adaptive Cruise Control (Advanced)
0 251 (If Equipped).
Forward Collision Alert (FCA) System
0 283 (If Equipped).
Heated Steering Wheel 082 (If
Equipped).
5. Instrument Cluster (Base Level) 088
or
Instrument Cluster (Uplevel) 090.
Driver Information Center (DIC)
Display. See Driver Information
Center (DIC) (Base Level) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
6. Steering Wheel Controls 0137 (If
Equipped).
7. Windshield Wiper/Washer 082. 8. Infotainment. See
Overview0135.
9. Light Sensor. See Automatic
Headlamp System 0128.
10. Hazard Warning Flashers 0129.
11. Dual Automatic Climate Control
System 0196.
12. Heated and Ventilated Front Seats
037 (If Equipped).
13. Lane Keep Assist (LKA) 0291 (If
Equipped).
14. Traction Control/Electronic Stability
Control 0239.
Stop/Start Disable Switch. See Stop/
Start System 0221.
Automatic Vehicle Hold (AVH) 0239.
MODE Button or
«/ªButton
(V-Series Only). See Driver Mode
Control 0241.
15. Wireless Charging Pad (If Equipped) (Out of View). See
Wireless Charging 085.
16. Park Assist Button. See Assistance
Systems for Parking or Backing
0 277. 17. Shift Lever. See
Automatic
Transmission (Mechanical Shifter)
0 227 or
Automatic Transmission (Electronic
Shifter) 0229.
18. ENGINE START/STOP Button. See Ignition Positions 0219.
19. Horn 082.
20. Steering Wheel Adjustment 082.
21. Head-Up Display (HUD) 0112 (If
Equipped).
22. Hood Release (Out of View). See Hood 0307.
23. Instrument Panel Illumination
Control 0130.
24. Data Link Connector (DLC) (Out of View). See Malfunction Indicator
Lamp (Check Engine Light) 097.
25. Electric Parking Brake 0237 (If
Equipped).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
KEYS, DOORS, AND WINDOWS 13
1. Press the button on the side of theremote key near the bottom and
pull the mechanical key out. Never
pull the mechanical key out
without pressing the button.
2. Use the mechanical key blade inthe slot to remove the battery
cover by hand.
3. Remove the seal by pulling on thetab to access the battery.
4. Remove the old battery. Do not use a metal object.
5. Insert the new battery, negative side facing down. Replace with a
CR2450 or equivalent battery.
6. Replace the seal, pushing it into the groove around the battery
compartment.
7. Replace the battery cover by snapping it back into the
remote key.
8. Reinsert the mechanical key.
Remote Vehicle Start
This feature allows the engine to be
started from outside the vehicle.
S: This button on the remote key is
for remote start.
The climate control system will use
the previous settings during a remote
start. The rear window defogger may
come on during remote start based on
cold ambient conditions. The rear
defog indicator light does not come on
during remote start.
If equipped, the heated and ventilated
front seats may also come on when
the vehicle personalization setting is
enabled. See Heated and Ventilated
Front Seats 037.
If equipped with a remote start heated
steering wheel, it may come on during
a remote start. See Heated Steering
Wheel 082.
Laws in some local communities may
restrict the use of remote starters. For
example, some laws may require a
person using remote start to have the
vehicle in view. Check local
regulations for any requirements.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
KEYS, DOORS, AND WINDOWS 23
Immobilizer Operation
This vehicle has a passive
theft-deterrent system.
The system does not have to be
manually armed or disarmed.
The vehicle is automatically
immobilized when the vehicle is
turned off.
The immobilization system is
disarmed when the ignition is turned
on or to ACC/ACCESSORY and a valid
remote key is present in the vehicle.
The security light, in the instrument
cluster, comes on if there is a problem
with arming or disarming the
theft-deterrent system.
The system has one or more remote
keys matched to an immobilizer
control unit in the vehicle. Only a
correctly matched remote key willstart the vehicle. If the remote key is
ever damaged, you may not be able to
start your vehicle.
When trying to start the vehicle, the
security light may come on briefly.
If the engine does not start and the
security light stays on, there is a
problem with the system. Turn the
ignition off and try again.
If the vehicle will not change ignition
modes (ACC/ACCESSORY, on, off), and
the remote key appears to be
undamaged, try another remote key.
Or, you may try placing the remote
key in the backup location. See
Remote Keyless Entry (RKE) System
Operation
07.
If the ignition modes will not change
with the other remote key or in the
backup location, the vehicle needs
service. If the ignition does change
modes, the first remote key may be
faulty. See your dealer.
It is possible for the immobilizer
system to learn new or replacement
remote keys. Up to eight remote keys
can be programmed for the vehicle. To
program additional remote keys, see “Programming Remote Keys to the
Vehicle
”under Remote Keyless Entry
(RKE) System Operation 07.
Do not leave the remote key or device
that disarms or deactivates the
theft-deterrent system in the vehicle.
Exterior Mirrors
Convex Mirrors
{Warning
A convex mirror can make things,
like other vehicles, look farther
away than they really are. If you cut
too sharply into the right lane, you
could hit a vehicle on the right.
Check the inside mirror or glance
over your shoulder before changing
lanes.
The passenger side mirror is convex
shaped. A convex mirror's surface is
curved so more can be seen from the
driver seat.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 81
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . . . . . 82
Steering Wheel Controls . . . . . . . . . . 82
Heated Steering Wheel . . . . . . . . . . . . 82
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Windshield Wiper/Washer . . . . . . . . 82
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Power Outlets . . . . . . . . . . . . . . . . . . . . . . 85
Wireless Charging . . . . . . . . . . . . . . . . . 85
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . . . 87
Instrument Cluster (Base Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Instrument Cluster (Uplevel) . . . . . 90
Speedometer . . . . . . . . . . . . . . . . . . . . . . . 93
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Trip Odometer . . . . . . . . . . . . . . . . . . . . . 93
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . 93
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 94
Engine Coolant Temperature
Gauge (Base Level) . . . . . . . . . . . . . . . 94 Engine Coolant Temperature
Gauge (Uplevel) . . . . . . . . . . . . . . . . . . 95
Seat Belt Reminders . . . . . . . . . . . . . . . 95
Airbag Readiness Light . . . . . . . . . . . . 96
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Charging System Light . . . . . . . . . . . . 97
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . . . . . 97
Brake System Warning Light . . . . . 99
Electric Parking Brake Light . . . . . 100
Service Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . 100
Performance Shifting Light . . . . . . 101
Automatic Vehicle Hold (AVH) Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Lane Keep Assist (LKA) Light . . . 101
Automatic Emergency Braking (AEB) Disabled Light . . . . . . . . . . . 101
Vehicle Ahead Indicator . . . . . . . . . 102
Pedestrian Ahead Indicator . . . . . . 102
Traction Off Light . . . . . . . . . . . . . . . . 102
StabiliTrak OFF Light . . . . . . . . . . . . 102
Traction Control System (TCS)/ StabiliTrak Light . . . . . . . . . . . . . . . . 103
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . 103
Driver Mode Control Light . . . . . . . 103 Tire Pressure Light . . . . . . . . . . . . . . . 104
Engine Oil Pressure Light . . . . . . . . 104
Low Fuel Warning Light . . . . . . . . . 105
Security Light . . . . . . . . . . . . . . . . . . . . . 105
High-Beam On Light . . . . . . . . . . . . . 105
Lamps On Reminder . . . . . . . . . . . . . 106
Cruise Control Light (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Cruise Control Light (Uplevel) . . . 106
Door Ajar Light . . . . . . . . . . . . . . . . . . . 107
Information Displays
Driver Information Center (DIC) (Base Level) . . . . . . . . . . . . . . . . . . . . . 107
Driver Information Center (DIC) (Uplevel) . . . . . . . . . . . . . . . . . . . . . . . . . 110
Head-Up Display (HUD) . . . . . . . . . 112
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . . . . . 116
Engine Power Messages . . . . . . . . . . 117
Vehicle Speed Messages . . . . . . . . . 117
Vehicle Personalization
Vehicle Personalization . . . . . . . . . . 117
Universal Remote System
Universal Remote System . . . . . . . . 122
Universal Remote System
Programming . . . . . . . . . . . . . . . . . . . 122
Universal Remote System Operation . . . . . . . . . . . . . . . . . . . . . . . . 124

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
INSTRUMENTS AND CONTROLS 87
indicated open source licenses (as are
included following this notice) for the
terms and conditions of their use.
OSS Notice Information
To obtain the source code that is
contained in this product, please visit
http://opensource.lge.com. In addition
to the source code, all referred license
terms, warranty disclaimers and
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cost of performing such distribution
(such as the cost of media, shipping,
and handling) upon email request to
[email protected]. This offer is
valid for three (3) years from the date
on which you purchased the product.
Freescale-WCT library
Copyright (c) 2012-2014 Freescale
Semiconductor, Inc.. All rights
reserved.1. Redistributions of source code must retain the above copyright
notice, this list of conditions and
the following disclaimer. 2. Redistributions in binary form
must reproduce the above
copyright notice, this list of
conditions and the following
disclaimer in the documentation
and/or other materials provided
with the distribution.
3. Neither the name of the copyright holder nor the names of its
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endorse or promote products
derived from this software without
specific prior written permission.
THIS SOFTWARE IS PROVIDED BY
THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY
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MERCHANTABILITY AND FITNESS
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PROCUREMENT OF SUBSTITUTE
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AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE
USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
Warning Lights, Gauges,
and Indicators
Warning lights and gauges can signal
that something is wrong before it
becomes serious enough to cause an
expensive repair or replacement.
Paying attention to the warning lights
and gauges could prevent injury.
Some warning lights come on briefly
when the engine is started to indicate
they are working. When one of the
warning lights comes on and stays on
while driving, or when one of the
gauges shows there may be a problem,
check the section that explains what
to do. Waiting to do repairs can be
costly and even dangerous.

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
98 INSTRUMENTS AND CONTROLS
require service. The light should come
on to show that it is working when
the ignition is in Service Mode. See
Ignition Positions0219.
Malfunctions are often indicated by
the system before any problem is
noticeable. Being aware of the light
and seeking service promptly when it
comes on may prevent damage.
Caution
If the vehicle is driven continually
with this light on, the emission
control system may not work as
well, the fuel economy may be
lower, and the vehicle may not run
smoothly. This could lead to costly
repairs that might not be covered
by the vehicle warranty.
Caution
Modifications to the engine,
transmission, exhaust, intake,
or fuel system, or the use of
replacement tires that do not meet
the original tire specifications, can
cause this light to come on. This
could lead to costly repairs not
covered by the vehicle warranty.
This could also affect the vehicle’s
ability to pass an Emissions
Inspection/Maintenance test. See
Accessories and Modifications 0306.
If the light is f lashing : A
malfunction has been detected that
could damage the emission control
system and increase vehicle
emissions. Diagnosis and service may
be required.
To help prevent damage, reduce
vehicle speed and avoid hard
accelerations and uphill grades.
If towing a trailer, reduce the amount
of cargo being hauled as soon as
possible. If the light continues to flash, find a
safe place to park. Turn the vehicle off
and wait at least 10 seconds before
restarting the engine. If the light is
still flashing, follow the previous
guidelines and see your dealer for
service as soon as possible.
If the light is on steady :
A
malfunction has been detected.
Diagnosis and service may be
required.
Check the following:
.If fuel has been added to the vehicle
using the capless fuel funnel
adapter, make sure that it has been
removed. See “Filling the Tank with
a Portable Gas Can ”under Filling the
Tank 0295. The diagnostic system
can detect if the adapter has been
left installed in the vehicle, allowing
fuel to evaporate into the
atmosphere. A few driving trips with
the adapter removed may turn off
the light.

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
116 INSTRUMENTS AND CONTROLS
Navigation Overlay :This displays
digital speed for Tour/ Sport, current
gear for Track, indicators from speed
view along with Turn-by-Turn
Navigation information in some
vehicles. The compass heading is
displayed when navigation routing is
not active.
Navigation Turn-by-Turn Alerts
shown in the instrument cluster may
also be displayed in any HUD view.
Care of the HUD
Clean the inside of the windshield to
remove any dirt or film that could
reduce the sharpness or clarity of the
HUD image.
Clean the HUD lens with a soft cloth
sprayed with glass cleaner. Wipe the
lens gently, then dry it.
HUD Troubleshooting
If you cannot see the HUD image
when the ignition is on, check that:
.Nothing is covering the HUD lens.
.The HUD brightness setting is not
too dim or too bright.
.The HUD is adjusted to the proper
height.
.Polarized sunglasses are not worn.
.The windshield and HUD lens are
clean.
If the HUD image is not correct,
contact your dealer.
The windshield is part of the HUD
system. If windshield replacement is
required, see Windshield Replacement
0 328.
Vehicle Messages
Messages displayed on the Driver
Information Center (DIC) indicate the
status of the vehicle or some action
that may be needed to correct a
condition. Multiple messages may
appear one after another.
The messages that do not require
immediate action can be
acknowledged and cleared by pressing
the thumbwheel. The messages that
require immediate action cannot be
cleared until that action is performed.
All messages should be taken
seriously; clearing the message does
not correct the problem. If a SERVICE message appears, see
your dealer.
Follow the instructions given in the
messages. The system displays
messages regarding the following
topics:
.Service Messages
.Fluid Levels
.Vehicle Security
.Brakes
.Steering
.Ride Control Systems
.Driver Assistance Systems
.Cruise Control
.Lighting and Bulb Replacement
.Wiper/Washer Systems
.Doors and Windows
.Seat Belts
.Airbag Systems
.Engine and Transmission
.Tire Pressure
.Battery