
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
254 Driving and Operating Warning (Continued).
Fuel can spray out if the
refueling nozzle is inserted
too quickly. This spray can
happen if the tank is nearly
full, and is more likely in hot
weather. Insert the refueling
nozzle slowly and wait for
any hiss noise to stop prior
to beginning to flow fuel.
If equipped, the fuel door is locked
when the vehicle doors are locked.
Press
K on the RKE transmitter to
unlock. To open the fuel door, push and
release the rearward center edge of
the door.
The vehicle has a capless refueling
system and does not have a fuel
cap. The filling nozzle must be fully
inserted and latched prior to starting
fuel flow.
{ WarningOverfilling the fuel tank by more
than three clicks of a standard fill
nozzle may cause:
.
Vehicle performance issues,
including engine stalling and
damage to the fuel system.
.
Fuel spills.
.
Potential fuel fires.
Be careful not to spill fuel. Wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care 0 333 .{ WarningIf a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Filling the Tank with a Portable
Gas Can
If the vehicle runs out of fuel and
must be filled from a portable
gas can:
1. Locate the capless funnel
adapter from under the carpet
in the trunk.
2. Insert and latch the funnel into
the capless fuel system.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Driving and Operating 255
{ WarningAttempting to refuel without using
the funnel adapter may cause fuel
spillage and damage the capless
fuel system. This could cause a
fire and you or others could be
badly burned and the vehicle
could be damaged.
3. After filling the tank, remove
and clean the funnel adapter
and return it to the storage
location.
Filling a Portable Fuel
Container
{ Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
(Continued) Warning (Continued) .
Use approved fuel
containers.
.
Remove the container from
the vehicle, trunk, or pickup
bed before filling.
.
Place the container on the
ground.
.
Place the nozzle inside the
fill opening of the container
before dispensing fuel, and
keep it in contact with the fill
opening until filling is
complete.
.
Fill the container no more
than 95% full to allow for
expansion.
.
Do not smoke, light
matches, or use lighters
while pumping fuel.
.
Avoid using cell phones or
other electronic devices.Trailer Towing General Towing
Information Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer. Read
the entire section before towing a
trailer.
For towing a disabled vehicle, see
Towing the Vehicle 0 330 . For
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing 0 331 .
Driving Characteristics
and Towing Tips Driving with a Trailer
When towing a trailer:
.
Become familiar with the state
and local laws that apply to
trailer towing.

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
284 Vehicle Care CautionIf brake fluid is spilled on the
vehicle's painted surfaces, the
paint finish can be damaged.
Immediately wash off any painted
surface.
Battery - North America The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid.
Refer to the replacement number
shown on the original battery label
when a new 12-volt battery is
needed.
The battery is in the trunk under the
spare tire. The vehicle has an
Absorbed Glass Mat (AGM) 12-volt
battery. Installation of a standard
12-volt battery will result in reduced
12-volt battery life.
When using a 12-volt battery
charger on the 12-volt AGM battery,
some chargers have an AGM
battery setting on the charger. If available, use the AGM setting on
the charger, to limit charge voltage
to 14.8 volts.
Stop/Start System
The vehicle has a Stop/Start system
to shut off the engine to help
conserve fuel. See Starting the
Engine 0 204 .
{ WarningWARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
HANDLING.
See California Proposition
65 Warning 0 262 . Vehicle Storage
{ WarningBatteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. See Jump Starting -
North America 0 327 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the
12-volt battery black, negative ( − )
cable from the battery to keep the
battery from running down.
Extended Storage: Remove the
12-volt battery black, negative ( − )
cable from the battery or use a
battery trickle charger.
Remember to reconnect the battery
when ready to drive the vehicle.
All-Wheel Drive If the vehicle is equipped with
All-Wheel Drive (AWD), this is an
additional system that needs
lubrication.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
292 Vehicle Care Number Usage
20 High-beam
headlamp relay
21 A/C clutch
22 –
23 Coolant heater
control module
24 Coolant pump
25 Coolant pump relay
26 HI fuel
27 Steering
column lock
28 Rear heated seats
29 Front heated seats
30 –
31 LED LGT BAT
32 A/C control
module/ –
33 AIR solenoid
34 –
35 Engine control
module Number Usage
36 Engine control
module 2
37 Coolant pump/
Ignition coils – odd
38 Ignition coils – even/
Non walk 2
39 Non walk
40 Instrument cluster
41 –
42 Fuel pump power
module
43 Instrument panel
body/Ignition
44 Aeroshutter
45 Washer
46 Front sensor
47 Left cornering LED
48 AIR solenoid relay
49 Air pump relay
50 Engine control
module relay
51 Wiper speed relay Number Usage
52 Wiper control relay
53 Headlamp control
relay
54 –
55 –
56 Air pump
57 –
58 Instrument panel
electronic center
59 –
60 ABS pump
61 Front wiper
62 Headlamp leveling
63 Electric brake
booster module
64 –
65 –
66 Transfer case
control module
67 Electric brake
booster

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 297Fuse Usage
F09 Passive entry/
Passive start
F10 Rear subwoofer am-
plifier
F11 Driver memory seat
module
F12 –
F13 –
F14 Right rear seat
F15 Left front amplifier
F16 Right front seat
F17 Rear heated seat
F18 Battery/Regulated
voltage control
F19 Door mirror switch
F20 –
F21 Vehicle integration
control module
F22 –
F23 Rear closure
F24 – Fuse Usage
F25 Left motorized
safety belt
pretensioner
F26 Rear defogger
F27 Right front amplifier
F28 Amplifier
F29 Sunroof
F30 Body control
module 2
F31 Body control
module 6
F32 Exterior rearview
mirror
F33 Right window
F34 Power trunk module
F35 On-board charging
module
F36 Alarm siren module
F37 DC AC inverter
F38 Rear blower
F39 Fuel pump power
F40 – Fuse Usage
F41 Rear seat power
outlet
F42 Left rear
memory seat
F43 –
F44 Rear closure
F45 Auxiliary audio/
Video/Radio
F46 External object
calculating/Side
blind zone alert/
Radar short range
sensor
F47 –
F48 Right front seat
F49 Memory bolster
module
F50 Body control
module 1
F51 Transmission
control module
F52 Parking assist

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
298 Vehicle Care Fuse Usage
F53 Heated, cooled or
ventilated seats (if
equipped)
F54 Rain sensor/Power
sounder/Intrusion/
Universal remote
system
F55 Front memory seat
module
F56 Evaporative
emissions leak
check module
F57 Voltage current
temperature module
F58 –
F59 Engine control
module power
F60 Right motorized
safety belt
pretensioner
F61 Parking lamps
F62 –
F63 – Fuse Usage
F64 Engine control
module/Ignition
F65 Rear glass
sunshade
F66 Rear vision camera/
Interior rearview
mirror
F67 DC DC converter/
Air quality sensor
F68 Damping control
module
F69 –
F70 –
F71 –
F72 –
F73 –
F74 –
F75 – Fuse Usage
Relays Usage
R1 Rear seat power
outlet relay
R2 Fuel pump relay
R3 Run/Crank relay

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
304 Vehicle Care (4) Construction Code :
A letter
code is used to indicate the type
of ply construction in the tire.
The letter R means radial ply
construction; the letter D means
diagonal or bias ply
construction; and the letter B
means belted-bias ply
construction.
(5) Rim Diameter :
Diameter of
the wheel in inches.
(6) Service Description :
These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions Air Pressure :
The amount of
air inside the tire pressing
outward on each square inch of the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Accessory Weight :
The
combined weight of optional
accessories. Some examples of
optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio :
The relationship
of a tire's height to its width.
Belt :
A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials.
Bead :
The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire :
A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread. Cold Tire Pressure :
The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch)
before a tire has built up heat
from driving. See Tire
Pressure 0 306 .
Curb Weight :
The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil,
and coolant, but without
passengers and cargo.
DOT Markings :
A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code
includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.