
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Instruments and Controls 143system monitoring the oil life,
additional maintenance is
recommended. See Maintenance
Schedule 0 344 .
The Oil Life display must be reset
after each oil change. It will not
reset itself. Do not reset the Oil Life
display accidentally at any time
other than when the oil has just
been changed. It cannot be reset
accurately until the next oil change.
To reset the engine oil life system,
press and hold SEL for several
seconds while the Oil Life display is
active. See Engine Oil Life
System 0 272 .
Tire Pressure : Shows the
approximate pressures of all four
tires. Tire pressure is displayed in
either kilopascal (kPa) or in pounds
per square inch (psi). If the pressure
is low, the value for that tire is
shown in amber. See Tire Pressure
Monitor System 0 308 and Tire
Pressure Monitor Operation 0 309 .
Vehicle Odometer (Base
Cluster) : Shows the odometer. Blank Page : Allows for no
information to be displayed in the
cluster info display areas.
Head-Up Display (HUD)
{ WarningIf the HUD image is too bright or
too high in your field of view, it
may take you more time to see
things you need to see when it is
dark outside. Be sure to keep the
HUD image dim and placed low in
your field of view.
If equipped with HUD, some
information concerning the
operation of the vehicle is projected
onto the windshield. The image is
projected through the HUD lens on
top of the instrument panel. The
information appears as an image
focused out toward the front of the
vehicle. CautionIf you try to use the HUD image
as a parking aid, you may
misjudge the distance and
damage your vehicle. Do not use
the HUD image as a parking aid.
The HUD information can be
displayed in various languages in
some vehicles. The speedometer
reading and other numerical values
can be displayed in either English or
metric units.
The language selection is changed
through the radio and the units of
measurement is changed through
the instrument cluster. See Vehicle
Personalization 0 157 and “ Cluster
Options Menu ” under Instrument
Cluster (Uplevel) 0 121 or
Instrument Cluster (Base
Level) 0 118 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
150 Instruments and Controls before filling to the recommended
level. If the oil is not low and this
message remains on, take the
vehicle to your dealer for service.
See Engine Oil 0 270 .
OIL PRESSURE LOW — TURN
VEHICLE OFF This message displays if low oil
pressure levels occur. Stop the
vehicle as soon as safely possible
and do not operate it until the cause
of the low oil pressure has been
corrected. Check the oil as soon as
possible and have the vehicle
serviced by your dealer.
Engine Power Messages ENGINE POWER IS REDUCED This message displays when the
vehicle's engine power is reduced.
Reduced engine power can affect
the vehicle's ability to accelerate.
If this message is on, but there is no
reduction in performance, proceed
to your destination. The
performance may be reduced the
next time the vehicle is driven. The
vehicle may be driven at a reduced speed while this message is on, but
maximum acceleration and speed
may be reduced. Anytime this
message stays on, the vehicle
should be taken to your dealer for
service as soon as possible.
Fuel System Messages FUEL LEVEL LOW This message displays when the
vehicle is low on fuel. Refuel as
soon as possible.
Key and Lock Messages NO REMOTE KEY WAS
DETECTED PLACE KEY IN
TRANSMITTER POCKET THEN
START YOUR VEHICLE This message displays when trying
to start the vehicle if an RKE
transmitter is not detected. The
transmitter battery may be weak.
See “ Starting the Vehicle with a Low
Transmitter Battery ” under Remote
Keyless Entry (RKE) System
Operation 0 29 . NO REMOTE DETECTED This message displays when the
transmitter battery may be weak.
See “ Starting the Vehicle with a Low
Transmitter Battery ” under Remote
Keyless Entry (RKE) System
Operation 0 29 .
NO REMOTE DETECTED
PRESS BRAKE TO RESTART This message displays when
attempting to turn off the vehicle
and the RKE transmitter is no longer
detected. Restarting is allowed
without the RKE transmitter for
five minutes. Press the brake pedal
and ENGINE START/STOP to
restart the vehicle.
NUMBER OF KEYS
PROGRAMMED This message displays when
programming new keys to the
vehicle.
REMOTE LEFT IN VEHICLE
This message displays when
leaving the vehicle with the RKE
transmitter still inside.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 261
Vehicle Care General Information General Information . . . . . . . . . . 262
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 262
California Perchlorate
Materials Requirements . . . . . 262
Accessories and
Modifications . . . . . . . . . . . . . . . . 262
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 263
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 264
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 265
Engine Oil . . . . . . . . . . . . . . . . . . . . 270
Engine Oil Life System . . . . . . . 272
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 273
Engine Air Cleaner/Filter . . . . . . 273
Cooling System . . . . . . . . . . . . . . 275
Engine Coolant . . . . . . . . . . . . . . . 277
Engine Overheating . . . . . . . . . . 280
Washer Fluid . . . . . . . . . . . . . . . . . 281
Brakes . . . . . . . . . . . . . . . . . . . . . . . 282
Brake Fluid . . . . . . . . . . . . . . . . . . . 283
Battery - North America . . . . . . 284
All-Wheel Drive . . . . . . . . . . . . . . . 284 Starter Switch Check . . . . . . . . . 285
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 285
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 286
Wiper Blade Replacement . . . . 286
Windshield Replacement . . . . . 287
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 287
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 288
LED Lighting . . . . . . . . . . . . . . . . . 288
License Plate Lamp . . . . . . . . . . 288
Replacement Bulbs . . . . . . . . . . . 289
Electrical System Electrical System Overload . . . 289
Fuses and Circuit Breakers . . . 290
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 299
All-Season Tires . . . . . . . . . . . . . . 300
Winter Tires . . . . . . . . . . . . . . . . . . 300 Low-Profile Tires . . . . . . . . . . . . . 300
Summer Tires . . . . . . . . . . . . . . . . 301
Tire Sidewall Labeling . . . . . . . . 301
Tire Designations . . . . . . . . . . . . . 303
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 304
Tire Pressure . . . . . . . . . . . . . . . . . 306
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor
Operation . . . . . . . . . . . . . . . . . . . 309
Tire Inspection . . . . . . . . . . . . . . . . 312
Tire Rotation . . . . . . . . . . . . . . . . . 313
When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . 314
Buying New Tires . . . . . . . . . . . . . 315
Different Size Tires and
Wheels . . . . . . . . . . . . . . . . . . . . . . 316
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 316
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . 318
Wheel Replacement . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . 319
If a Tire Goes Flat . . . . . . . . . . . . 320
Tire Changing . . . . . . . . . . . . . . . . 321
Compact Spare Tire . . . . . . . . . . 326

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
266 Vehicle Care 1. Engine Coolant Surge Tank
and Pressure Cap. See
Cooling System 0 275 .
2. Engine Air Cleaner/Filter 0 273 .
3. Engine Oil Fill Cap. See
Engine Oil 0 270 .
4. Engine Cooling Fan (Out of
View). See Cooling
System 0 275 .
5. Engine Oil Dipstick. See
Engine Oil 0 270 .
6. Remote Positive (+) Battery
Terminal. See Jump Starting -
North America 0 327 .
7. Engine Compartment Fuse
Block 0 290 .
8. Brake Fluid Reservoir (Under
Cover). See Brake Fluid 0 283 .
9. Windshield Washer Fluid
Reservoir. See Washer
Fluid 0 281 .
10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0 327 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
268 Vehicle Care 1. Engine Coolant Surge Tank
and Pressure Cap. See
Cooling System 0 275 .
2. Engine Air Cleaner/Filter 0 273 .
3. Engine Cooling Fan (Out of
View). See Cooling
System 0 275 .
4. Engine Oil Fill Cap. See
Engine Oil 0 270 .
5. Engine Oil Dipstick. See
Engine Oil 0 270 .
6. Remote Positive (+) Battery
Terminal. See Jump Starting -
North America 0 327 .
7. Engine Compartment Fuse
Block 0 290 .
8. Brake Fluid Reservoir. See
Brake Fluid 0 283 .
9. Windshield Washer Fluid
Reservoir. See Washer
Fluid 0 281 .
10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0 327 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
270 Vehicle Care 1. Engine Coolant Surge Tank
and Pressure Cap. See
Cooling System 0 275 .
2. Engine Air Cleaner/Filter 0 273 .
3. Engine Cooling Fan (Out of
View). See Cooling
System 0 275 .
4. Engine Oil Fill Cap. See
Engine Oil 0 270 .
5. Engine Oil Dipstick. See
Engine Oil 0 270 .
6. Remote Positive (+) Battery
Terminal. See Jump Starting -
North America 0 327 .
7. Engine Compartment Fuse
Block 0 290 .
8. Brake Fluid Reservoir. See
Brake Fluid 0 283 .
9. Windshield Washer Fluid
Reservoir. See Washer
Fluid 0 281 .
10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0 327 . 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 0 272 .
.
Always dispose of engine oil
properly. See “ What to Do with
Used Oil ” in this section.
Checking Engine Oil
It is a good idea to check the engine
oil level at each fuel fill. In order to
get an accurate reading, the vehicle must be on level ground. The
engine oil dipstick handle is a loop.
See Engine Compartment Overview
0 265 for the location of the engine
oil dipstick.
1. If the engine has been running
recently, turn off the engine and
allow several minutes for the oil
to drain back into the oil pan.
Checking the oil level too soon
after engine shutoff will not
provide an accurate oil level
reading.
{ WarningThe engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.
2. Pull out the dipstick and wipe it
with a clean paper towel or
cloth, then push it back in all
the way. Remove it again,
keeping the tip down, and
check the level.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
278 Vehicle Care Checking Coolant The vehicle must be on a level
surface when checking the coolant
level.
2.0L L4 and 3.0L V6 Engine
Coolant Surge Tank 3.6L V6 Engine Coolant
Surge Tank
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. See Engine
Overheating 0 280 .
The coolant surge tank is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment
Overview 0 265 . How to Add Coolant to the
Coolant Surge Tank
CautionThis vehicle has a specific
coolant fill procedure. Failure to
follow this procedure could cause
the engine to overheat and be
severely damaged.
If no problem is found, check to see
if coolant is visible in the coolant
surge tank. If coolant is visible but
the coolant level mark is not visible,
add a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant at the coolant surge tank to
the top rib on the middle of the tank,
but be sure the cooling system,
including the coolant surge tank
pressure cap, is cool before this is
done. See Engine
Overheating 0 280 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 279
{ WarningSteam and scalding liquids from a
hot cooling system can blow out
and burn you badly. Never turn
the cap when the cooling system,
including the surge tank pressure
cap, is hot. Wait for the cooling
system and surge tank pressure
cap to cool.
{ WarningAdding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or others
(Continued) Warning (Continued) could be burned. Use a 50/
50 mixture of clean, drinkable
water and DEX-COOL coolant.
CautionIn cold weather, water can freeze
and crack the engine, radiator,
heater core, and other parts. Use
the recommended coolant and
the proper coolant mixture.
{ Warning
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol
and it will burn if the engine parts
are hot enough. Do not spill
coolant on a hot engine.
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about
one-quarter of a turn. If you
hear a hiss, wait for that to
stop. This will allow any
pressure still left to be vented
out the discharge hose.
2. Keep turning the pressure cap
slowly and remove it.
3. Fill the coolant surge tank with
the proper mixture to the
indicated level mark.
4. With the coolant surge tank
pressure cap off, start the
engine and let it run until you
can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
indicated level mark.