service CADILLAC CT6 2020 Owner's Guide

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
124 INSTRUMENTS AND CONTROLS
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 0260. 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. .
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. See Recommended
Fuel (3.6L V6 Engine) 0258 or
Recommended Fuel (4.2L Twin
Turbo V8 Engine) 0259.
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 0269.
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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
INSTRUMENTS AND CONTROLS 125
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.
The brake system warning light may
also come on when the parking brake
is set, if the vehicle has low brake
fluid, or if the brakes are severely
faded. If the brakes are overheated,
DIC messages may display, and the
vehicle speed may be limited. If the
brake fluid is not low, if the brakes are
not overheated, and if the parking
brake is fully released, then the vehicle has a brake problem. Have the
vehicle brake system serviced as soon
as possible.
If the light comes on while driving,
pull off the road and stop carefully.
If equipped with 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 take longer
to stop. If the light is still on, have the
vehicle towed for service. See
Towing
the Vehicle 0346.
{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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
126 INSTRUMENTS AND CONTROLS
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. SeeElectric Parking Brake
0 200. 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.
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.
See
Brake System Warning Light 0125.
Gear Shifting Light
If equipped, this light will display
when Performance Algorithm Liftfoot
(PAL) or Performance Algorithm Shift
(PAS) is activated. See Driver Mode
Control 0204.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
128 INSTRUMENTS AND CONTROLS
Traction Off Light
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer. If the system is working
normally, the indicator light then
turns off. For vehicles with a
reconfigurable cluster, this light is in
the display area and it may not come
on when the ignition is turned on.
The traction off light comes on when
the Traction Control System (TCS) has
been turned off by pressing and
releasing the TCS/StabiliTrak/ESC
button.
This light and the StabiliTrak/ESC OFF
light come on when StabiliTrak/
Electronic Stability Control (ESC) is
turned off.
If the TCS is off, wheel spin is not
limited. Adjust driving accordingly.See
Traction Control/Electronic Stability
Control 0203.
StabiliTrak OFF Light
This light comes on briefly while
starting the engine. If it does not,
have the vehicle serviced by your
dealer.
This light comes on when the
StabiliTrak/Electronic Stability Control
(ESC) system is turned off.
If StabiliTrak/ESC is off, the Traction
Control System (TCS) is also off.
If StabiliTrak/ESC and TCS are off, the
system does not assist in controlling
the vehicle. Turn on the TCS and the
StabiliTrak/ESC systems, and the
warning light turns off.
See Traction Control/Electronic Stability
Control 0203.
Traction Control System
(TCS)/StabiliTrak Light
This light comes on briefly when the
engine is started.
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 have been disabled.
A Driver Information Center (DIC)
message may display. Check the DIC
messages to determine which
feature(s) is no longer functioning and
whether the vehicle requires service.
If the light is on and flashing, the TCS
and/or the StabiliTrak/ESC system is
actively working.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
INSTRUMENTS AND CONTROLS 129
SeeTraction Control/Electronic Stability
Control 0203.
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
(Continued)
Caution (Continued)
and it may not be covered by the
vehicle warranty. SeeEngine
Overheating 0288.
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 0288.
Driver Mode Control Light
This light comes on when Sport Mode
is selected.
This light comes on when Snow/Ice
Mode is selected.
This light comes on when Track Mode
is selected.
See Driver Mode Control 0204.
Tire Pressure Light

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
130 INSTRUMENTS AND CONTROLS
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. SeeTire Pressure 0322.
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 0325.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.
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
This light is near the fuel gauge and
comes on briefly when the ignition is
turned on as a check to show it is
working. For vehicles with a
reconfigurable cluster, this light is in
the display area and may not come on
when the ignition is turned on.
It also comes on when the fuel tank is
low on fuel. The light turns off when
fuel is added. If it does not, have the
vehicle serviced.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
INSTRUMENTS AND CONTROLS 131
Security Light
On some vehicles the immobilizer
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.
For vehicles with the reconfigurable
cluster, this light may not come on
when the engine is started.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system. SeeImmobilizer Operation
0 32.
High-Beam On Light
This light comes on when the
high-beam headlamps are in use. See
Headlamp High/Low-Beam Changer
0151.
IntelliBeam Light
This light comes on when the
IntelliBeam system, if equipped, is
enabled. See Exterior Lamp Controls
0 149.
Lamps On Reminder
This light comes on when the exterior
lamps are in use. See Exterior Lamp
Controls 0149.
Cruise Control Light
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 0209.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
INSTRUMENTS AND CONTROLS 139
Vehicle Messages
Messages displayed on the 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
SEL. 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
Engine Power Messages
ENGINE POWER IS REDUCED
This message displays when the
vehicle's propulsion power is reduced.
A reduction in propulsion power can
affect the vehicle's ability to
accelerate. If this message is on, but
there is no observed reduction in
performance, proceed to your
destination. The performance may be
reduced the next time the vehicle is driven. The vehicle may be driven
while this message is on, but
maximum acceleration and speed may
be reduced. Anytime this message
stays on, or displays repeatedly, the
vehicle should be taken to your dealer
for service as soon as possible.
Under certain operating conditions,
propulsion will be disabled. Try
restarting after the vehicle has been
off for 30 seconds.
Vehicle Speed Messages
SPEED LIMITED TO XXX
KM/H (MPH)
This message shows that the vehicle
speed has been limited to the speed
displayed. The limited speed is a
protection for various propulsion and
vehicle systems, such as lubrication,
brakes, thermal, suspension, Teen
Driver if equipped, or tires.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
158 CLIMATE CONTROLS
Climate Controls
Climate Control Systems
Automatic Climate ControlSystem (Dual Zone) . . . . . . . . . . . . 158
Automatic Climate Control System (Quad Zone) . . . . . . . . . . . . 163
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170
Climate Control Systems
Automatic Climate Control System (Dual Zone)
The climate control buttons on the center stack and on the climate control
display are used to adjust the heating, cooling, and ventilation.
Center Stack Climate Controls
1. Driver and Passenger Temperature Controls
2. Fan Control
3. Driver and Passenger Heated and Ventilated Seats (If Equipped)
4. Rear Window Defogger 5. Defrost
6. OFF (Fan)
7. Recirculation
8. AUTO (Automatic Operation)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
170 CLIMATE CONTROLS
.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 airflow
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 Schedule 0359.
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
0359.