Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
324 VEHICLE CARE
.A fluid leak in the brake hydraulic
system. Have the brake hydraulic
system fixed. With a leak, the
brakes will not work well.
Always clean the brake fluid reservoir
cap and the area around the cap
before removing it.
Do not top off the brake fluid. Adding
fluid does not correct a leak. If fluid is
added when the linings are worn,
there will be too much fluid when
new brake linings are installed. Add or
remove fluid, as necessary, only when
work is done on the brake hydraulic
system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You or
others could be burned, and the
vehicle could be damaged. Add
brake fluid only when work is done
on the brake hydraulic system. When the brake fluid falls to a low
level, the brake warning light comes
on. See
Brake System Warning Light
0 145.
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid at
the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule 0390.
What to Add
Use only GM approved DOT 3 (for
gasoline only vehicles) or DOT 4 (for
PLUG-IN vehicles) brake fluid from a
clean, sealed container. See
Recommended Fluids and Lubricants
0 399.{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If 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.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
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VEHICLE CARE 325
Stop/Start System
The vehicle has a Stop/Start system to
shut off the engine to help conserve
fuel.
SeeStarting the Engine (PLUG-IN Only)
0 218 orStarting the Engine (Gasoline
Only) 0221.
{Warning
WARNING: 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. For
more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition 65 Warning
0 297 and the back cover.
PLUG-IN Vehicle
The PLUG-IN vehicle 12-volt battery is
in the trunk. PLUG-IN vehicles also
have a high voltage battery. Only a
trained service technician with the
proper knowledge and tools should
inspect, test, or replace the high
voltage battery. See your dealer if
either the 12-volt or the high voltage
battery needs service. The dealer has
information on how to recycle the
high voltage battery.
{Warning
Damage to the high voltage battery
or high voltage system can create a
risk of electric shock, overheating,
or fire.
If the vehicle is damaged from a
moderate to severe crash, flood,
fire, or other event, the vehicle
should be inspected as soon as
possible. Until the vehicle has been
inspected, store it outside at least
15 m (50 ft) from any structure or
(Continued)
Warning (Continued)
anything that can burn. Ventilate
the vehicle by opening a window or
a door.
Contact your dealer as soon as
possible to determine whether an
inspection is needed.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode. You
can be badly hurt if you are not
careful. SeeJump Starting - North
America 0374 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.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
326 VEHICLE CARE
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.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check
the transfer case fluid unless a leak is
suspected or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.How to Check Lubricant1. Fill Plug
2. Drain Plug
To get an accurate reading, the vehicle
should be on a level surface.
If the level is below the bottom of the
fill plug hole on the transfer case,
some lubricant will need to be added.
Add enough lubricant to raise the
level to the bottom of the fill plug
hole. Use care not to overtighten the
fill plug.What to Use
To determine what kind of lubricant
to use, see
Recommended Fluids and
Lubricants 0399.
Starter Switch Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake. Do
not use the accelerator pedal,
and be ready to turn off the
engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 327
Automatic Transmission
Shift Lock Control Function
Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Electric Parking Brake 0235.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check, the
vehicle could begin to move. You or
others could be injured and
property could be damaged. Make
sure there is room in front of the
vehicle in case it begins to roll. Be
ready to apply the regular brake at
once should the vehicle begin
to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping your
foot on the regular brake, set the
parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only. .
To check the P (Park) mechanism's
holding ability: With the engine
running, shift to P (Park). Then
release the parking brake followed
by the regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear or cracking.
For the proper type and size, see
Maintenance Replacement Parts 0400.
To replace the wiper blade assembly: 1. Pull the windshield wiper assembly away from the
windshield.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
332 VEHICLE CARE
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace a
bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another
fuse location, if a fuse goes out.
Replace the fuse as soon as possible.
Engine Compartment Fuse
Block
The underhood fuse block is on the
driver side of the engine
compartment.
Lift the fuse block cover to access the
fuses.
The vehicle may not be equipped with
all of the fuses and relays shown.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
334 VEHICLE CARE
FusesUsage
20 High-beam headlamp relay
21 Air conditioning 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 lighting battery
32 Air conditioning control module
33 AIR solenoid
34 –
35 Engine control module Fuses
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 Fuses
Usage
52 Wiper control relay
53 Headlamp control relay
54 –
55 –
56 Air pump
57 –
58 Instrument panel electronic center
59 –
60 Anitlock brake system 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-11292458) -
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VEHICLE CARE 339
FusesUsage
F28 Amplifier
F29 Sunroof
F30 Body control module 2
F31 Body control module 6
F32 Exterior heated mirrors
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 –
F41 Rear seat power outlet
F42 Left rear memory seat
F43 – Fuses
Usage
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
F53 Ventilated seats
F54 Headliner
F55 Front memory seat module
F56 Evaporative emissions leak check
module Fuses
Usage
F57 Voltage current temperature module
F58 –
F59 Engine control module battery
F60 Right motorized seat belt pretensioner
F61 Parking lamps
F62 –
F63 –
F64 Engine control module ignition
F65 Rear window sunshade
F66 Rear vision camera/ Interior rearview
mirror
F67 DC DC converter/Air quality sensor
F68 Damping control module
F69 Television tuner module
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VEHICLE CARE 345
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire and
Rim Association.
(2) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from sidewall
to sidewall.
(3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size aspect
ratio is 60, as shown in item 3 of
the illustration, it would mean
that the tire's sidewall is
60 percent as high as it is wide.
(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 0347.
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.