coolant CADILLAC CTS 2018 User Guide

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
VEHICLE CARE 269
Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always have
the air cleaner/filter in place when
driving.
Cooling System
The cooling system allows the engine
to maintain the correct working
temperature.
2.0L L4 Engine (LTG)
1. Engine Coolant Surge Tankand Pressure Cap
2. Engine Cooling Fan (Out of View)
3.6L V6 Engine (LGX)
1. Engine Coolant Surge Tank
and Pressure Cap
2. Engine Cooling Fan (Out of View)

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
270 VEHICLE CARE
3.6L V6 Engine (LF3)
1. Engine Coolant Surge Tankand Pressure Cap
2. Engine Cooling Fan (Out of View)
6.2L V8 Engine (LT4)
1. Engine Coolant Surge Tank
and Pressure Cap
2. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan can start
up even when the engine is not
running and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine coolant.
See Maintenance Schedule 0339 and
Recommended Fluids and Lubricants
0 348.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating, see
Engine Overheating 0274.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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What to Use
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down to
−37 °C (−34 °F), outside
temperature.
. Gives boiling protection up to
129 °C (265 °F), engine
temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.
. Helps keep the proper engine
temperature.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard GMW3420 and
clean, drinkable water. Anything
else can cause damage to the
engine cooling system and the
vehicle, which would not be covered
by the vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level. It is normal to see coolant moving in
the upper coolant hose return line
when the engine is running. It is also
normal to see bubbles entering the
surge tank through the small hose.
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.If coolant is visible but the coolant
level is not at or above the indicated
mark, add a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
272 VEHICLE CARE
Be sure the cooling system is cool
before this is done.
It is normal for the coolant level in
the bottom chamber to rise and fall
with operating temperature and
ambient conditions. Coolant will
evaporate from the bottom chamber
in normal operation. This will happen
faster when the vehicle is driven for
long periods in hot, dry conditions.
If no coolant is visible in the coolant
surge tank, add coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{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
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
{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.
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but the
coolant level is not at the bottom of
the fill neck, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
coolant at the coolant surge tank, but
be sure the cooling system, including
the coolant surge tank pressure cap, is
cool before you do it.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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1. Remove the coolant surge tankpressure cap from the top
chamber 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. 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. Open the
surge tank service port cap to
the lower chamber. The service
port is behind the top chamber.
3. Fill the surge tank top chamberwith the proper mixture to the
bottom of the fill neck. The top
chamber needs to be completely
full. Fill the surge tank bottom
chamber through the service port
to approximately half.
4. With the coolant surge tank pressure cap off and the surge
tank service port cap open, start
the engine and let it run until
you can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fan(s).
By this time, the coolant level
inside the coolant surge tank top
chamber may be lower. If the level is lower, add more of the
proper mixture to the surge tank
top chamber until the level
reaches the bottom of the
fill neck.
5. Replace the surge tank pressure cap tightly and close the surge
tank service port cap.
6. Check the level in the surge tank top and bottom chambers when
the cooling system has cooled
down. If the coolant is not at the
proper levels, repeat Steps 1–
6 and reinstall the pressure cap
and close the service port. If the
coolant still is not at the proper
levels 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.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Engine Overheating
The vehicle has an indicator to warn
of the engine overheating.
If the decision is made not to lift the
hood when this warning appears, get
service help right away. SeeRoadside
Service 0361.
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.
If Steam Is Coming from the
Engine Compartment with No
Overheat Warning
(V-Series Only)
The V-Series hood vent is functional,
and will allow water from rain and car
washes to enter the engine
compartment and contact hot
surfaces. If steam is seen coming from
the hood vent with no accompanying
overheat warning, no action is
required.
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 overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
VEHICLE CARE 275
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. SeeEngine Compartment
Overview 0256 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)
Caution (Continued)
.Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank only
three-quarters full when it is
very cold. This allows for
fluid expansion if freezing
occurs, which could damage
the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
288 VEHICLE CARE
FusesUsage
22 Driver motorized seat belt
26 –
27 –/Heated seat 2
28 –/Reverse lock out
29 Adaptive forward lighting, Automatic
headlamp leveling/
Pedestrian protection
30 –
31 Passenger window switch
32 –
33 Sunroof
34 Front wiper
35 Steering column lock
36 Rear bussed electrical center/Ignition
37 –/Malfunction
Indicator Lamp/
Ignition
38 Aeroshutter Fuses
Usage
39 O2 sensor/Emissions
40 Ignition coil even/O2 sensor
41 Ignition coil odd
42 Engine control module
43 –
44 –
45 Washer
48 Instrument panel/ Body/Ignition
49 Fuel system control module/Ignition
50 Heated steering wheel
51 Engine control module/Ignition
52 Transmission control module/Ignition
53 Coolant pump
55 – Fuses
Usage
56 Transmission control module
64 Adaptive headlamp leveling
65 Left HID headlamp
66 Right HID headlamp
67 Left/Right high-beam headlamp
68 Headlamp leveling motor
69 Horn
71 Cooling fan
72 Starter 2
73 Brake vacuum pump
74 Starter 1
75 Air conditioning clutch
76 –
Relays Usage
8 Headlamp washer
23 Wiper control

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
VEHICLE CARE 289
RelaysUsage
24 Wiper speed
25 Engine control module
46 Rear washer
47 Front washer
54 Coolant pump
57 Low-beam headlamp relay
58 High-beam headlamp
59 Run/Crank
60 Starter 2
61 Vacuum pump
62 Starter 1
63 Air conditioning control
70 HornInstrument Panel Fuse
Block
The instrument panel fuse block is in
the end of the driver side of the
instrument panel.
To access the fuses, remove the end
panel by gently prying with a plastic
tool near each clip, beginning at the
point shown.
To install the end cover, insert the
tabs on the back of the cover into the
slots in the instrument panel at the
points shown. Align the clips with the
slots in the instrument panel, and
press the cover into place.
The vehicle may not be equipped with
all of the fuses and relays shown.

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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 0301. 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.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code includes
the Tire Identification Number
(TIN), an alphanumeric designator
which can also identify the tire
manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 188.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0188.