ECU CADILLAC XT6 2020 Service Manual

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
DRIVING AND OPERATING 179
weight of the driver, passengers,
and cargo should never exceed the
vehicle's capacity weight.
Certification/Tire Label
Label Example
A vehicle-specific Certification/
Tire label is attached to the center
pillar (B-pillar).
The label may show the size of the
vehicle's original tires and the
inflation pressures needed to
obtain the gross weight capacity
of the vehicle. The label shows the
gross weight capacity of the
vehicle. This is called the GrossVehicle Weight Rating (GVWR).
The GVWR includes the weight of
the vehicle, all occupants, fuel,
and cargo.
The Certification/Tire label may
also show the maximum weights
for the front and rear axles, called
the Gross Axle Weight Rating
(GAWR). To find out the actual
loads on the front and rear axles,
weigh the vehicle at a weigh
station. Your dealer can help with
this. Be sure to spread the load
equally on both sides of the
centerline.
Caution
Overloading the vehicle may cause
damage. Repairs would not be
covered by the vehicle warranty. Do
not overload the vehicle.
{Warning
Things inside the vehicle can
strike and injure people in a
sudden stop or turn, or in a
crash.
.Put things in the cargo
area of the vehicle. In the
cargo area, put them as far
forward as possible. Try to
spread the weight evenly.
.Never stack heavier things,
like suitcases, inside the
vehicle so that some of
them are above the tops of
the seats.
.Do not leave an unsecured
child restraint in the
vehicle.
.Secure loose items in the
vehicle.
.Do not leave a seat folded
down unless needed.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
246 DRIVING AND OPERATING
If equipped with Lane Change Alert
(LCA), the LCA detection zones that
extend back from the side of the
vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic
Alert (RCTA), use caution while
backing up when towing a trailer, as
the RCTA detection zones that extend
out from the back of the vehicle do
not move further back when a trailer
is towed.
{Warning
To prevent serious injury or death
from carbon monoxide (CO), when
towing a trailer:. Do not drive with the liftgate,
trunk/hatch, or rear-most
window open.
. Fully open the air outlets on
or under the instrument
panel.
(Continued)
Warning (Continued)
.Adjust the climate control
system to a setting that
brings in only outside air. See
“Climate Control Systems” in
the Index.
For more information about carbon
monoxide, see Engine Exhaust
0 189.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as responsive
as the vehicle itself. Get used to the
handling and braking of the
combination by driving on a level road
surface before driving on public roads.
The trailer structure, the tires, and the
brakes must be all be rated to carry
the intended cargo. Inadequate trailer
equipment can cause the combination
to operate in an unexpected or unsafe
manner. Before driving, inspect all
trailer hitch parts and attachments,
safety chains, electrical connectors,
lamps, tires, and mirrors. See Towing
Equipment 0252. If the trailer has electric brakes, start the combination
moving and then manually apply the
trailer brake controller to check the
trailer brakes work. During the trip,
occasionally check that the cargo and
trailer are secure and that the lamps
and any trailer brakes are working.
Towing with a Stability Control
System
When towing, the stability control
system might be heard. The system
reacts to vehicle movement caused by
the trailer, which mainly occurs
during cornering. This is normal when
towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving without a trailer. This can help
to avoid heavy braking and sudden
turns.
Passing
More passing distance is needed when
towing a trailer. The combination of
the vehicle and trailer will not
accelerate as quickly and is much
longer than the vehicle alone. It is

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
272 VEHICLE CARE
3. Fill the coolant surge tank withthe proper mixture to the mark
pointed to on the front of the
coolant surge tank.
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 fans. 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 mark pointed to on the front
of the coolant surge tank.
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.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.
Engine Overheating
The vehicle has several indicators to
warn of the engine overheating.
There is an engine coolant
temperature gauge on the instrument
cluster. See Engine Coolant Temperature
Gauge 0117. 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 0353.
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 XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
278 VEHICLE CARE
Front Wiper Blade Replacement
To replace the wiper blade assembly:1. Pull the windshield wiper assembly away from the
windshield.
2. Lift up on the latch in the middle
of the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm.
4. Remove the wiper blade. 5. Reverse Steps 1–3 for wiper
blade replacement.
Rear Wiper Blade Replacement
To remove the wiper blade:
1. Put the vehicle in ACC/ACCESSORY and turn on the rear
windshield wiper. The wiper will
stop pointing down. See Rear
Window Wiper/Washer 0107.
2. Push the ENGINE START/STOP button to turn the vehicle off.
3. Lift the wiper arm away from the window.
4. Push the release lever (2) to disengage the hook and push the
wiper arm (1) out of the blade
assembly (3). 5. Push the new blade assembly
securely on the wiper arm until
the release lever clicks into place.
6. Start the engine and the rear wiper will return to its normal
position.
Windshield Replacement
HUD System
The windshield is part of the HUD
system. If the windshield needs to be
replaced, be sure to get one that is
designed for HUD or the HUD image
may look out of focus.
Driver Assistance Systems
If the windshield needs to be replaced
and the vehicle is equipped with a
front camera sensor for the Driver
Assistance Systems, a GM
replacement windshield is
recommended. The replacement
windshield must be installed
according to GM specifications for
proper alignment. If it is not, these
systems may not work properly, they

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
310 VEHICLE CARE
Caution
If the vehicle is equipped with a tire
size other than 265/45R21, use tire
chains only where legal and only
when necessary. Use low profile
chains that add no more than
12 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
front axle. Do not use chains on the
tires of the rear 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. SeeTires0289. If air goes out of a tire, it is much
more likely to leak out slowly. But if
there ever is 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
(Continued)
Warning (Continued)
underinflated or flat may cause a
blowout and a serious crash. Never
attempt to re-inflate a tire that has
been driven on while severely
underinflated or flat. Have your
dealer or an authorized tire service
center repair or replace the flat tire
as soon as possible.
{Warning
Lifting a vehicle and getting under
it to do maintenance or repairs is
dangerous without the appropriate
safety equipment and training. If a
jack is provided with the vehicle, it
is designed only for changing a flat
tire. If it is used for anything else,
you or others could be badly injured
or killed if the vehicle slips off the
jack. If a jack is provided with the
vehicle, only use it for changing a
flat tire.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
316 VEHICLE CARE
To store the flat tire:
1. Remove the cable package fromunder the spare tire, jack, and
tools.
2. Remove the small cap by tapping the back of the cap with the
extension of the shaft, if the
vehicle has aluminum wheels.
3. Put the jack, tool container, and cargo management system tray
back in their original location.
4. Put the flat tire in the cargo bin with the valve stem facing the
rear of the vehicle. 5. Pull the cable through the door
striker and the center of the
wheel.
6. Open the lift gate to 3 / 4 door
location and adjust the door
automatically or manually until
there is enough space to hook
the cable to the door hinges. See
Liftgate 021.
7. Hook the other end of the cable onto the outside portion of the
liftgate hinge on the other side of
the vehicle.
8. Pull on the cable to make sure it is secure.
9. Make sure the metal tube is
centered at the striker. Push the
tube toward the front of the
vehicle.
10. Close the liftgate and make sure it is fully latched.
The compact spare is for temporary
use only. Replace the compact spare
tire with a full-size tire as soon as
possible.
Storing the Compact Spare Tire
and Tools
To store the spare tire and tools: 1. Open the liftgate. See Liftgate
0 21.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
320 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
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. Do not
drag a locked wheel/tire. Use tire
skates or dollies under any locked
wheel/tire while loading the vehicle.
Do not use a sling type lift to tow
the vehicle. This could damage the
vehicle.
Caution
If the vehicle cannot be shifted into
Neutral (N), do not use the tow eye
to tow the vehicle. Vehicle damage
may occur.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
322 VEHICLE CARE
Dinghy Towing
Caution
If the vehicle is towed with all four
wheels on the ground, the
drivetrain components could be
damaged. The repairs would not be
covered by the vehicle warranty. Do
not tow the vehicle with all four
wheels on the ground.The vehicle is not designed to be
towed with all four wheels on the
ground. If the vehicle must be towed,
a dolly should be used. See the
following information on dolly towing.
Dolly Towing
Driving onto a Dolly
1. Park the vehicle on level ground in front of the dolly and turn the
vehicle off.
2. Make sure the parking brake is released.
3. Press and hold ENGINE START/ STOP with your foot off the
brake for five seconds. 4. Hold the brake pedal and press
the parking brake switch for
15 seconds until the service
parking brake light flashes.
5. While the service parking brake light is still flashing, remove
your foot from the brake pedal
and release the parking brake
switch.
6. Immediately press and release the parking brake switch again
while the service park brake light
is still flashing.
7. Start the vehicle and drive onto the dolly.
8. Place the vehicle in P (Park).
9. Turn off the vehicle.
10. Open the hood.
11. Exit the vehicle and secure the vehicle onto the dolly.
12. Disconnect the negative (–) terminal connector from the
12-volt battery.
13. Close the hood of the vehicle.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
VEHICLE CARE 323
Removing the Vehicle from a Dolly1. Make sure the vehicle is secured to the dolly.
2. Open the door and open the hood of the vehicle.
3. Connect the negative (–) terminal connector from the
12-volt battery.
4. Press and hold ENGINE START/ STOP with your foot off the
brake for five seconds.
5. Hold the brake pedal and press the parking brake switch for
five seconds until the parking
brake light flashes.
6. Turn the vehicle off.
7. Unsecure the vehicle and remove it from the dolly.
8. Do not drive in Service Mode with the parking brake setTowing the Vehicle from
the RearCaution
Towing the vehicle from the rear
could damage it. Also, repairs would
not be covered by the vehicle
warranty. Never have the vehicle
towed from the rear.
Do not tow the vehicle from the rear.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-12984300) -
2020 - CRC - 3/19/19
VEHICLE CARE 331
{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.
Removing and Replacing the
Floor Mats
The driver side floor mat is held in
place by two button-type retainers.
1. Pull up on the rear of the driver
side floor mat to unlock each
retainer and remove.
2. Reinstall by lining up the floor mat retainer openings over the
carpet retainers and snapping
into position.
3. Make sure the floor mat is properly secured in place. Verify
the floor mat does not interfere
with the pedals.