2018 CADILLAC CT6 air filter

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
CLIMATE CONTROLS 191
Climate Controls
Climate Control Systems
Automatic Climate ControlSystem (Dual Zone - Gasoline
and PLUG-IN) . . . . . . . . . . . . . . . . . . . 191
Automatic Climate Control System (Quad Zone -
Gasoline Only) . . . . . . . . . . . . . . . . . . 197
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Climate Control Systems
Automatic Climate Control System (Dual Zone - Gasoline
and PLUG-IN)
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-11292458) -
2018 - crc - 2/14/17
204 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 0390.
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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
296 VEHICLE CARE
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 297
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 297
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 297
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 298
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 298
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 300
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 307
Engine Oil Life System . . . . . . . . . . . 309
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Engine Air Cleaner/Filter . . . . . . . . . 311
Cooling System (Gasoline Only) . . . . . . . . . . . . . . . . . 312
Cooling System (PLUG-IN Only) . . . . . . . . . . . . . . . . . 316
Engine Overheating . . . . . . . . . . . . . . 321
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 322
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 323 Battery - North America . . . . . . . . . 324
All-Wheel Drive . . . . . . . . . . . . . . . . . . 326
Starter Switch Check . . . . . . . . . . . . . 326
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . 327
Wiper Blade Replacement . . . . . . . 327
Windshield Replacement . . . . . . . . 328
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 328
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . . . . . 329
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 330
LED Lighting . . . . . . . . . . . . . . . . . . . . . 330
License Plate Lamp . . . . . . . . . . . . . . 330
Replacement Bulbs . . . . . . . . . . . . . . . 330
Electrical System
Electrical System Overload . . . . . . 331
Fuses and Circuit Breakers . . . . . . 331
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Instrument Panel Fuse Block . . . . 335
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340 All-Season Tires . . . . . . . . . . . . . . . . . . 341
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 341
Low-Profile Tires . . . . . . . . . . . . . . . . . 342
Summer Tires . . . . . . . . . . . . . . . . . . . . 342
Tire Sidewall Labeling . . . . . . . . . . . 342
Tire Designations . . . . . . . . . . . . . . . . . 344
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 345
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 347
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 349
Tire Pressure Monitor System . . . 349
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 350
Tire Inspection . . . . . . . . . . . . . . . . . . . 353
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 353
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Buying New Tires . . . . . . . . . . . . . . . . 355
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Uniform Tire Quality Grading . . . 357
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 359
Wheel Replacement . . . . . . . . . . . . . . 359
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 360
If a Tire Goes Flat . . . . . . . . . . . . . . . . 360
Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 362
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 368

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 301
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Oil Fill Cap. See Engine Oil
0 307.
4. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir (Under Cover). See Brake Fluid0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 303
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Traction Power Inverter Module (TPIM).
3. High Voltage DC Cables.
4. TPIM Coolant Reservoir and Pressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
5. High Voltage AC Cables.
6. Engine Air Cleaner/Filter 0311.
7. Engine Oil Fill Cap. See Engine Oil
0 307.
8. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
9. Engine Oil Dipstick. See Engine
Oil 0307.
10. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374. 11.
Engine Compartment Fuse Block
0332.
12. Brake Fluid Reservoir (Under Cover). See Brake Fluid0323.
13. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322.
14. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0374.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 305
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 307
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
. Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” later in
this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0309.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick
handle is a loop. See Engine
Compartment Overview 0300 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
310 VEHICLE CARE
oil as soon as possible within the next
1 000 km (600 mi). It is possible that,
if driving under the best conditions,
the oil life system might indicate that
an oil change is not necessary for up
to a year. The engine oil and filter
must be changed at least once a year
and at this time the system must be
reset. Your dealer has trained service
people who will perform this work and
reset the system. It is also important
to check the oil regularly over the
course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally,
the oil must be changed at 5 000 km
(3,000 mi) since the last oil change.
Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
Reset the system whenever the engine
oil is changed so that the system can
calculate the next engine oil change.
To reset the system:1. Using the DIC buttons, display REMAINING OIL LIFE on the
DIC. See Driver Information Center
(DIC) 0162. 2. Press and hold SEL to clear the
CHANGE ENGINE OIL SOON
message and reset the oil life
at 100%.
Be careful not to reset the oil life
display accidentally at any time
other than after the oil is
changed. It cannot be reset
accurately until the next oil
change.
The oil life system can also be reset as
follows: 1. Using the DIC buttons, display REMAINING OIL LIFE on the
DIC. See Driver Information Center
(DIC) 0162.
2. Fully press and release the accelerator pedal three times
within five seconds.
If the CHANGE ENGINE OIL
SOON message is not on, the
system is reset.
The system is reset when the
CHANGE ENGINE OIL SOON message
is off. If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not been reset. Repeat the
procedure.
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak occurs,
take the vehicle to your dealer and
have it repaired as soon as possible.
The vehicle is not equipped with a
transmission fluid level dipstick.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, this should be
done at the dealer. Contact your dealer
for additional information.