2018 CADILLAC CT6 ECU

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
320 VEHICLE CARE
The coolant reservoir for the TPIM is
filled with GM Premix DEX-COOL
coolant. SeeRecommended Fluids and
Lubricants 0399. If using this mixture,
nothing else needs to be added.
The coolant needs to be replaced at
the appropriate interval. See
Maintenance Schedule 0390.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level.
The coolant reservoir is in the engine
compartment. See Engine Compartment
Overview 0300.
Check to see if coolant is visible in the
reservoir. If coolant is visible but the
coolant level is below the indicated
mark, there could be a leak in the
cooling system.
Caution
Do not run the engine when there
is a leak in the PLUG-IN cooling
system. This can cause a loss of all
coolant and can damage the system
and the vehicle. Have any leaks
fixed right away.
How to Add Coolant to the
Coolant Reservoir
If no problem is found, add the proper
DEX-COOL coolant mixture at the
coolant reservoir.
The coolant reservoir pressure cap can
be removed when the cooling system,
including the pressure cap, is no
longer hot.
1. Turn the pressure cap counterclockwise and remove it.
2. Fill the coolant reservoir with the proper mixture to the indicated
mark on the side of the reservoir.
3. Reinstall the pressure cap tightly.
Caution
If the pressure caps are not secured
and tightened properly, coolant loss
and damage to the PLUG-IN cooling
systems or vehicle may occur. Make
sure the caps are properly and
tightly secured.
Check the level in the coolant
reservoir when the cooling system has
cooled down. If the coolant is not at
the proper level, repeat Steps 1 and 2,
then reinstall the pressure cap. If the
coolant still is not at the proper level
when the system cools down again,
see your dealer.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
360 VEHICLE CARE
Tire Chains
{Warning
If the vehicle has 265/45R18 size
tires on the rear axle, do not use
tire chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage to
the brakes, suspension, or other
vehicle parts. The area damaged by
the tire chains could cause loss of
control and a crash. Use another
type of traction device only if its
manufacturer recommends it for
the vehicle's tire size combination
and road conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the traction
device if it contacts the vehicle. Do
not spin the wheels. If traction
devices are used, install them on
the rear tires.
Caution
If the vehicle is equipped with a tire
size other than 265/45R18 on the
rear, use tire chains only where
legal and only when necessary. Use
low profile chains that add no more
than 10 mm thickness to the tire
tread and inner sidewall. Use chains
that are the proper size for the tires.
Install them on the tires of the rear
axle. Do not use chains on the tires
of the front axle. Tighten them as
tightly as possible with the ends
securely fastened. Drive slowly and
follow the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues, slow
down until it stops. Driving too fast
or spinning the wheels with chains
on will damage the vehicle.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires are
maintained properly. SeeTires0340.
If air goes out of a tire, it is much more likely to leak out slowly. But if
there is ever a blowout, here are a few
tips about what to expect and what
to do:
If a front tire fails, the flat tire creates
a drag that pulls the vehicle toward
that side. Take your foot off the
accelerator pedal and grip the steering
wheel firmly. Steer to maintain lane
position, and then gently brake to a
stop, well off the road, if possible.
A rear blowout, particularly on a
curve, acts much like a skid and may
require the same correction as used in
a skid. Stop pressing the accelerator
pedal and steer to straighten the
vehicle. It may be very bumpy and
noisy. Gently brake to a stop, well off
the road, if possible.
{Warning
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash. Never
(Continued)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
372 VEHICLE CARE
17. Lower the jack all the way andremove the jack from under the
vehicle.
18. Tighten the wheel nuts firmly with the wheel wrench.
Storing a Flat or Spare Tire and
Tools
{Warning
Storing a jack, a tire, or other
equipment in the passenger
compartment of the vehicle could
cause injury. In a sudden stop or
collision, loose equipment could
strike someone. Store all these in
the proper place.
To store the flat tire and tools: 1. Open the trunk.
2. Replace the jack and tools as they were, originally, stored in
their container near the
spare tire.
3. Replace the spare tire cover.
4. Place the tire, lying flat, in the rear storage compartment. If there is a loop on the end of
the strap used to secure the flat
tire, go to Step 5. If there is not a
loop, go to Step 8.
5. Route the loop end of the
strap (3) through one of the
cargo tie-downs (1) in the rear of
the vehicle.
6. Route the hook (2) through the loop (3).
7. Pull the strap to tighten it around the cargo tie-down (1).
8. Route the hook end of the strap
through the wheel.
9. Attach the hook to the cargo tie-down in the rear of the
vehicle.
10. Tighten the strap.
The compact spare is for temporary
use only. Replace the compact spare
tire with a full-size tire as soon as
you can.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
376 VEHICLE CARE
6. Connect the other end of the redpositive (+) cable to the
positive (+) terminal of the good
battery.
7. Connect one end of the black negative (–) cable to the
negative (–) terminal of the good
battery.
8. Connect the other end of the black negative (–) cable to the
remote negative (–) ground
terminal on the driver side shock
tower for the discharged battery.
9. Start the engine in the vehicle with the good battery and run
the engine at idle speed for at
least four minutes.
10. Try to start the vehicle that had the dead battery. If it will not
start after a few tries, it probably
needs service.
Caution
If the jumper cables are connected
or removed in the wrong order,
electrical shorting may occur and
(Continued)
Caution (Continued)
damage the vehicle. The repairs
would not be covered by the vehicle
warranty. Always connect and
remove the jumper cables in the
correct order, making sure that the
cables do not touch each other or
other metal.
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle and
removing the jumper cables, allow it
to idle for several minutes.
Towing the Vehicle
Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty.
Do not lash or hook to suspension
components. Use the proper straps
around the tires to secure the
vehicle.
Use only a flatbed tow truck for
towing a disabled vehicle. Never use a
sling type lift or damage will occur.
Use ramps to help reduce approach
angles if necessary. A towed vehicle
should have its drive wheels off the
ground. Consult a professional towing
service if the disabled vehicle must be
towed.
If the vehicle is equipped with a tow
eye, only use the tow eye to pull the
vehicle onto a flatbed car carrier from
a flat road surface. Do not use the tow
eye to pull the vehicle from snow,
mud, or sand.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 379
Caution
Use of a shield mounted in front of
the vehicle grille could restrict
airflow and cause damage to the
transmission. The repairs would not
be covered by the vehicle warranty.
If using a shield, only use one that
attaches to the towing vehicle.
Dolly Towing (Rear-Wheel Drive
Vehicles)
To dolly tow a rear-wheel drive vehicle
from the rear:1. Attach the dolly to the tow vehicle following the dolly
manufacturer instructions.
2. Put the rear wheels on the dolly.
3. Shift the transmission to P (Park).
4. Firmly set the parking brake.
5. Use an adequate clamping device designed for towing to ensure
that the front wheels are locked
into the straight-ahead position.
6. Secure the vehicle to the dolly following the manufacturer
instructions.
7. Release the parking brake only after the vehicle being towed is
firmly attached to the towing
vehicle.
8. Turn the ignition off.Dolly Towing (All-Wheel Drive
Vehicles)
Vehicles with All-Wheel Drive cannot
be dolly towed.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 387
Care of Seat Belts
Keep belts clean and dry.
{Warning
Do not bleach or dye seat belt
webbing. It may severely weaken
the webbing. In a crash, they might
not be able to provide adequate
protection. Clean and rinse seat belt
webbing only with mild soap and
lukewarm water. Allow the webbing
to dry.
Floor Mats
{Warning
If a floor mat is the wrong size or is
not properly installed, it can
interfere with the pedals.
Interference with the pedals can
cause unintended acceleration and/
or increased stopping distance
which can cause a crash and injury.
Make sure the floor mat does not
interfere with the pedals.Use the following guidelines for
proper floor mat usage.
.
The original equipment floor mats
were designed for your vehicle.
If the floor mats need replacing, it
is recommended that GM certified
floor mats be purchased. Non-GM
floor mats may not fit properly
and may interfere with the pedals.
Always check that the floor mats
do not interfere with the pedals.
. Do not use a floor mat if the
vehicle is not equipped with a
floor mat retainer on the driver
side floor.
. Use the floor mat with the correct
side up. Do not turn it over.
. Do not place anything on top of
the driver side floor mat.
. Use only a single floor mat on the
driver side.
. Do not place one floor mat on top
of another.
The driver side floor mat is held in
place by two button-type retainers.
Removing and Replacing the
Floor Mats
1. Pull up on the rear of the floor mat to unlock the retainers and
remove.
2. Reinstall by lining up the floor mat retainer openings over the
carpet retainers and snap into
position.
3. Make sure the floor mat is properly secured in place. Verify
the floor mat does not interfere
with the pedals.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
412 CUSTOMER INFORMATION
Coverage
Services are provided for the duration
of the vehicle’s powertrain warranty.
In the U.S., anyone driving the vehicle
is covered. In Canada, a person driving
the vehicle without permission from
the owner is not covered.
Roadside Service is not a part of the
New Vehicle Limited Warranty.
General Motors North America and
Cadillac reserve the right to make any
changes or discontinue the Roadside
Service program at any time without
notification.
General Motors North America and
Cadillac reserve the right to limit
services or payment to an owner or
driver if they decide the claims are
made too often, or the same type of
claim is made many times.
Cadillac Owner Privileges
.Emergency Fuel Delivery:
Delivery of enough fuel for the
vehicle to get to the nearest
service station. .
Lock-Out Service: Service to
unlock the vehicle if you are
locked out. A remote unlock may
be available if you have OnStar.
For security reasons, the driver
must present identification before
this service is given.
. Emergency Tow from a Public
Road or Highway: Tow to the
nearest Cadillac dealer for
warranty service, or if the vehicle
was in a crash and cannot be
driven. Assistance is not given
when the vehicle is stuck in the
sand, mud, or snow.
. Flat Tire Change: Service to
change a flat tire with a spare tire.
The spare tire, if equipped, must
be in good condition and properly
inflated. It is your responsibility
for the repair or replacement of
the tire if it is not covered by the
warranty.
. Battery Jump Start: Service to
jump start a dead battery.
. Trip Interruption Benefits and
Service: If your trip is interrupted
due to a warranty failure,
incidental expenses may be reimbursed during the Powertrain
warranty period. Items considered
are hotel, meals, and rental car or
a vehicle being delivered back to
the customer, up to 805 km
(500 mi).
Cadillac Technician Roadside
Service (U.S. Only)
Cadillac's exceptional Roadside Service
is more than an auto club or towing
service. It provides every Cadillac
owner in the United States with the
advantage of contacting a Cadillac
advisor and, where available, a
Cadillac trained dealer technician who
can provide on-site service.
A dealer technician will travel to your
location within a 30-mile radius of a
participating Cadillac dealership.
If beyond this radius, we will arrange
to have your car towed to the nearest
Cadillac dealership. Each technician
travels with a specially equipped
service vehicle complete with the
necessary Cadillac parts and tools
required to handle most roadside
repairs.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
ONSTAR 421
OnStar
OnStar Overview
OnStar Overview . . . . . . . . . . . . . . . . . . 421
OnStar Services
Emergency . . . . . . . . . . . . . . . . . . . . . . . . 422
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Navigation . . . . . . . . . . . . . . . . . . . . . . . . 423
Connections . . . . . . . . . . . . . . . . . . . . . . 423
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . 425
OnStar Additional Information
OnStar AdditionalInformation . . . . . . . . . . . . . . . . . . . . . 426
OnStar Overview
=Voice Command Button
QBlue OnStar Button
>Red Emergency Button
This vehicle may be equipped with a
comprehensive, in-vehicle system that
can connect to an OnStar Advisor for
Emergency, Security, Navigation,
Connections, and Diagnostics Services.
OnStar services may require a paid
subscription and data plan. OnStar
requires the vehicle battery and
electrical system, cellular service, and
GPS satellite signals to be available
and operating. OnStar acts as a link to
existing emergency service providers.
OnStar may collect information about
you and your vehicle, including
location information. See OnStar User
Terms, Privacy Statement, and
Software Terms for more details including system limitations at
www.onstar.com (U.S.) or
www.onstar.ca (Canada).
The OnStar system status light is next
to the OnStar buttons. If the status
light is:
.
Solid Green: System is ready.
. Flashing Green: On a call.
. Red: Indicates a problem.
. Off: System is active. PressQ
twice to speak with an OnStar
Advisor.
Press
Qor call 1-888-4ONSTAR
(1-888-466-7827) to speak to an
Advisor.
Press
=to:
. Make a call, end a call, or answer
an incoming call.
. Give OnStar Hands-Free Calling
voice commands.
. Give OnStar Turn-by-Turn
Navigation voice commands.
. Obtain and customize the Wi-Fi
hotspot name or SSID and
password, if equipped.