Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 305
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 307
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
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 0309.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick
handle is a loop. See Engine
Compartment Overview 0300 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 315
3.6L V6 Engine Coolant Surge Tank
Check to see if coolant is visible in the
coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. See Engine Overheating
0 321.
The coolant surge tank is in the
engine compartment on the passenger
side of the vehicle. See Engine
Compartment Overview 0300.
How to Add Coolant to the
Coolant Surge Tank
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but not at or above the indicated mark, add a 50/
50 mixture of clean, drinkable water
and DEX-COOL coolant. Be sure the
cooling system, including the coolant
surge tank pressure cap, is cool before
this is done. See
Engine Overheating
0 321.
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.
{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.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant is
not visible in the surge tank,
contact your dealer.
1. Remove the coolant surge tank
pressure 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.
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
318 VEHICLE CARE
The coolant surge tank is in the
engine compartment on the passenger
side of the vehicle. SeeEngine
Compartment Overview 0300.
How to Add Coolant to the
Coolant Surge Tank
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but not at or
above the indicated mark, add GM
Premix DEX-COOL coolant. Be sure
the cooling system, including the
coolant surge tank pressure cap, is
cool before this is done. See Engine
Overheating 0321.
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.
{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.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant is
not visible in the surge tank,
contact your dealer.
1. Remove the coolant surge tank
pressure 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
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) -
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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
330 VEHICLE CARE
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs 0330.
For any bulb-changing procedure not
listed in this section, contact your
dealer.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly not listed here, contact your
dealer.
License Plate Lamp
Lamp Assembly
To replace one of these lamps:
1. Push the lamp assembly toward the center of the vehicle.
2. Pull the lamp assembly down to expose the LED connector.
3. Pull the retaining tab on the LED connector up to release the lamp
assembly. Remove the lamp
assembly.
4. Install the new lamp assembly on the LED connector. Push in
the retaining tab to lock the new
lamp assembly in place. 5. Push the lamp assembly back
into position until the release tab
locks into place.
Replacement Bulbs
Exterior Lamp Bulb Number
License Plate Lamp 13588150
For replacement bulbs not listed here,
contact your dealer.
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.