Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 311
1. Remove the coolant surge tankpressure 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.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.
If the coolant still is not at the
proper level when the system
cools down again, see your
dealer.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
2.0L L4 Engine Only - Automatic
Coolant Service Fill Instructions
If equipped, this feature assists in
filling and removing air from the
cooling system after service of
components or when coolant is added
after being too low.
To activate the fill and air removal
process:
1. With a cold system, add coolant to the COLD FILL mark on the
surge tank.
2. Replace the cap on the surge tank.
3. Connect the vehicle to a battery charger.
4. Turn the ignition to Service Mode. See Ignition Positions
0 201.
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator and the brake for
two seconds, then release.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
312 VEHICLE CARE
At the end of the cycle, check the
coolant level in the surge tank and
add coolant if it is low. Turn off the
vehicle, allow the Electronic Control
Module (ECM) to go to sleep, about
2 minutes, and repeat Steps 4-7.
Listen for pump activation and
movement of the control valves while
watching the level of the coolant in
the surge tank. If the tank empties,
turn the ignition off, carefully remove
the surge tank cap, refill to the COLD
FILL mark, and repeat Steps 4-7. The
fill and air removal process will run
for approximately 10 minutes.
4.2L V8 Engine OnlyCaution
This vehicle has a specific coolant
fill procedure. Failure to follow this
procedure could cause the engine to
overheat and be severely damaged.
See your dealer for assistance.
Because of possible engine failure or
damage if performed without the
proper tools and information, engine coolant should only be added
by a qualified technician. See your
dealer.
Engine Overheating
The vehicle has several indicators to
warn of the engine overheating.
There is an engine coolant
temperature gauge and an engine
coolant temperature warning light on
the instrument cluster. See
Engine
Coolant Temperature Gauge 0135 and
Engine Coolant Temperature Warning
Light 0146. The vehicle may also
display a message on the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears, get
service help right away. See Roadside
Service 0405.
If the decision is made to lift the
hood, make sure the vehicle is parked
on a level surface. Then check to see if
the engine cooling fan is running.
If the engine is overheating, the fan
should be running. If it is not, do not
continue to run the engine. Have the
vehicle serviced.
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all coolant
and can damage the system and
vehicle. Have any leaks fixed
right away.
If Steam Is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure cap,
even a little, can cause them to
come out at high speed and you
could be burned. Never turn the cap
when the cooling system, including
the pressure cap, is hot. Wait for
the cooling system and pressure
cap to cool.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 313
If No Steam Is Coming from the
Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen or
heard, the problem may not be too
serious. Sometimes the engine can get
a little too hot when the vehicle:
.Climbs a long hill on a hot day
. Stops after high-speed driving
. Idles for long periods in traffic
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the engine coolant temperature
gauge is no longer in the overheated
area or the engine coolant
temperature warning light no longer
displays, the vehicle can be driven. Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
distance from the vehicle in front.
If the warning does not come back on,
continue to drive normally and have
the cooling system checked for proper
fill and function.
If the warning continues, pull over,
stop, and park the vehicle right away.
If there is no sign of steam, idle the
engine for three minutes while parked.
If the warning is still displayed, turn
off the engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an area
where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full. See
Engine Compartment
Overview 0292 for reservoir location.
Caution
.
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
(Continued)
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 325
FusesUsage
22 Transmission auxiliary oil pump
cooling
23 –
24 Cabin heater pump
26 Engine control module ignition
27 Steering column lock ignition
28 Rear heated seats ignition
29 Front heated seats ignition
30 –
31 Headlamp/Daytime running lamps/Right
headlamp
32 –
33 –
34 –
35 Engine control module ignition –2 Fuses
Usage
36 Engine control module ignition –1
37 Coolant pump/ Ignition coils –odd
38 Ignition coils –even/
Non walk 2
39 Non walk
40 Electric brake control module1/Instrument
cluster/central
gateway module
ignition
41 –
42 Fuel tank zone module/Ignition
43 Heated steering wheel module/
Reflective light aux
display/HVAC IGN/
Automatic occupant
sensing display
44 Aeroshutter
45 Washer Fuses
Usage
46 Front short range radar sensors
47 Left cornering LED
54 –
55 –
56 –
57 –
58 –
59 –
60 Antilock brake system pump/Electric
brake control
module–1
61 Front wiper
62 Headlamp leveling
63 –
64 –
66 Transfer case control module
67 –
68 –
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
330 VEHICLE CARE
FusesUsage
F26 Charge air coolant pump
F27 Engine control module ignition –2
F28 –
F29 –
Relays Usage
R1 Headlamp/Daytime running lamps
R2 Air conditioning control
R3 Starter motor
R4 Starter pinion
R5 Cabin heater pump
R6 Engine control module
R7 –
R8 –Instrument Panel Fuse
Block
The instrument panel fuse block is
behind the driver side instrument
panel storage compartment.
The storage compartment has a press
to open latch. To access the fuses,
open the compartment by pressing
and releasing near the top center
square.
Apply pressure to the two retaining
tabs on the sides of the compartment,
until the two retaining tabs clear the
sides of the instrument panel. Allow
the compartment to move downward,
and out of the way.
To reinstall the compartment, reverse
the steps.
The vehicle may not be equipped with
all of the fuses shown.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
SERVICE AND MAINTENANCE 383
Maintenance Schedule
Owner Checks and Services
At Each Fuel Stop
.Check the engine oil level. See
Engine Oil 0299.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0346.
. Inspect the tires for wear. See Tire
Inspection 0353.
. Check the windshield washer fluid
level. See Washer Fluid 0313.
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the engine
oil life system may not indicate the
need for vehicle service for up to a
year. The engine oil and filter must be
changed at least once a year and the
oil life system must be reset. Your
trained dealer technician can perform
this work. If the engine oil life system is reset accidentally, service the
vehicle within 5 000 km/3,000 mi since
the last service. Reset the oil life
system when the oil is changed. See
Engine Oil Life System
0302.
Air Conditioning Desiccant
(Replace Every Seven Years)
The air conditioning system requires
maintenance every seven years. This
service requires replacement of the
desiccant to help the longevity and
efficient operation of the air
conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0353.
. Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0299
and
Engine Oil Life System 0302. .
Inspect the engine air filter and
check the air filter life percentage.
If necessary, replace engine air
filter and reset the Engine Air
Filter Life System. See Engine Air
Cleaner/Filter 0304 and
Engine Air Filter Life System 0304.
. Check engine coolant level. See
Cooling System 0307.
. Check windshield washer fluid
level. See Washer Fluid 0313.
. Check tire inflation pressures. See
Tire Pressure 0346.
. Inspect tire wear. See Tire
Inspection 0353.
. Visually check for fluid leaks.
. Inspect brake system. See Exterior
Care 0372.
. Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0372.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
392 SERVICE AND MAINTENANCE
Recommended Fluids, Lubricants, and Parts
Recommended Fluids and Lubricants
UsageFluid/Lubricant
Automatic Transmission DEXRON-ULV Automatic Transmission Fluid (GM Part No. 19352619, in Canada 19352620).
Engine Coolant 50/50 mixture of clean drinkable water and use only DEX-COOL Coolant.
Engine Oil (Except 4.2L V8 Twin Turbo Engine) Engine oil meeting the dexos1 specification of the proper SAE viscosity grade.
ACDelco dexos1 full synthetic is recommended. See
Engine Oil0299.
Engine Oil (4.2L V8 Twin Turbo Engine Only) Engine oil meeting the dexos2 specification of the proper SAE viscosity grade.
ACDelco dexos2 is recommended. See
Engine Oil0299.
Hood Latch Assembly, Pivots, Spring Anchor, and Release Pawl Lubriplate Lubricant Aerosol (GM Part No. 89021668, in Canada 89021674) or
lubricant meeting requirements of NLGI #2, Category LB or GC-LB.
Hydraulic Brake System DOT 3 Hydraulic Brake Fluid (GM Part No. 19353126, in Canada 19353127).
Key Lock Cylinders, Hood and Door Hinges Multi-Purpose Lubricant, Superlube (GM Part No. 12346241, in
Canada 10953474).
Rear Axle (Except V-Series)/Front Axle SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88863089, in Canada 88863090).
Rear Axle (V-Series) SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88862624, in
Canada 88862625).
Transfer Case (All-Wheel Drive) Transfer Case Fluid (GM Part No. 19331044, in Canada 19331045).
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
428 INDEX
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Cluster, Instrument . . . . . . . . . . . .127, 130
Collision Damage Repair . . . . . . . . . . . 408
Compact Spare Tire . . . . . . . . . . . . . . . . . 366
CompartmentsStorage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Connected Services
Connections . . . . . . . . . . . . . . . . . . . . . . . 423
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . 425
Navigation . . . . . . . . . . . . . . . . . . . . . . . . . 422
Connections Connected Services . . . . . . . . . . . . . . . 423
Control Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Control of a Vehicle . . . . . . . . . . . . . . . . 191
Convenience Net . . . . . . . . . . . . . . . . . . . . 117
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . 52
Coolant Engine Temperature Gauge . . . . . . 135
Engine Temperature Warning
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Cooling . . . . . . . . . . . . . . . . . . . . . . . . .175, 180
Cooling System . . . . . . . . . . . . . . . . . . . . . 307
Cornering Lamps . . . . . . . . . . . . . . . . . . . 170
Courtesy Lamps . . . . . . . . . . . . . . . . . . . . . 171 Courtesy Transportation
Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . 227 Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Cruise Control, Adaptive . . . . . . . . . . . 229
Cruise Control, Super . . . . . . . . . . . . . . . 237
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Customer Assistance . . . . . . . . . . . . . . . 403 Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Text Telephone (TTY) Users . . . . . 403
Customer Information
Publications OrderingInformation . . . . . . . . . . . . . . . . . . . . . . 410
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 401
D
Damage Repair, Collision . . . . . . . . . . . 408
Danger, Warning, and Caution . . . . . . . . 2
Data CollectionInfotainment System . . . . . . . . . . . . . 413
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
Data Recorders, Event . . . . . . . . . . . . . . 412
Daytime Running Lamps (DRL) . . . 168
Defensive Driving . . . . . . . . . . . . . . . . . . . 191
Delayed Locking . . . . . . . . . . . . . . . . . . . . . 40
Diagnostics Connected Services . . . . . . . . . . . . . . . 425 Distracted Driving . . . . . . . . . . . . . . . . . . 190
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . 171
Door
Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . . 149
Delayed Locking . . . . . . . . . . . . . . . . . . . . 40
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . 40
Rear Seat Pass-Through . . . . . . . . . . . . 75
Drive Belt Routing, Engine . . . . . . . . . 399
Drive Systems All-Wheel Drive . . . . . . . . . . . . . . 216, 317
Driver Assistance Systems . . . . . . . . . 252
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . . . . . . . 150
Driver Mode Control . . . . . . . . . . . . . . . . 222
Driver Mode Control Light . . . . . . . . . 146
Driving Assistance Systems . . . . . . . . . . . . . . . 262
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . 281
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
For Better Fuel Economy . . . . . . . . . . . 27
Hill and Mountain Roads . . . . . . . . 194
If the Vehicle is Stuck . . . . . . . . . . . . 196
Loss of Control . . . . . . . . . . . . . . . . . . . . 193
Off-Road Recovery . . . . . . . . . . . . . . . . 192
Track Events and Competitive . . . 193