2009 CADILLAC CTS cooling

Cooling System
The cooling system allows the engine to maintain the
correct working temperature.
When you decide it is safe to lift the hood, here is what
you will see:
A. Electric Engine Cooling Fan(s) (Out of View)
B. Coolant Surge Tank and Pressure Cap{CAUTION:
An electric engine cooling fan under the hood 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.
{CAUTION:
Heater and radiator hoses, and other engine parts,
can be very hot. Do not touch them. If you do, you
can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine re, and you could be burned.
Get any leak xed before you drive the vehicle.
Notice:Using coolant other than DEX-COOL
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL
®(silicate-free) coolant in
the vehicle.
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Engine Coolant
The cooling system in the vehicle for all engines and
the intercooler is lled with DEX-COOL®. This coolant is
designed to remain in the vehicle for ve years or
150,000 miles (240 000 km), whichever occurs rst.
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, seeEngine
Overheating on page 5-37.
What to Use
{CAUTION:
Adding only plain water to the cooling system can
be dangerous. Plain water, or some other liquid
such as alcohol, can boil before the proper coolant
mixture will. The vehicle’s coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could get
too hot but you would not get the overheat
warning. The engine could catch re and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant.Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
Gives freezing protection down to−34°F (−37°C),
outside temperature.
Gives boiling protection up to 265°F (129°C),
engine temperature.
Protects against rust and corrosion.
Will not damage aluminum parts.
Helps keep the proper engine temperature.
Notice:If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice:If extra inhibitors and/or additives are used
in the vehicle’s cooling system, the vehicle could
be damaged. Use only the proper mixture of
the engine coolant listed in this manual for the
cooling system. SeeRecommended Fluids and
Lubricants on page 6-14for more information.
5-32

Checking Coolant (CTS)
The vehicle must be on a level surface when checking
the coolant level.
The engine coolant reservoir is located in the engine
compartment on the driver side of the vehicle. See
Engine Compartment Overview on page 5-14.
Check to see if coolant is visible in the surge tank.
If the coolant inside the 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 FULL COLD
mark, add a 50/50 mixture of clean, drinkable water
and DEX-COOL
®coolant at the coolant surge tank,
but be sure the cooling system is cool before this
is done. SeeEngine Coolant on page 5-32for more
information.
If the engine is warm or hot, the coolant level should be
at or above the FROID/FULL COLD line on the side
of the coolant surge tank. If the engine is cold, the
coolant level should be near the FROID/FULL COLD
line on the side of the coolant surge tank. If it is
not, there could be a leak in the cooling system.
How to Add Coolant to the Surge Tank
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot enough.
Do not spill coolant on a hot engine.
Notice:This vehicle has a specic coolant ll
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
{CAUTION:
An electric engine cooling fan under the hood 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.
5-33

{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They are
under pressure, and if you turn the surge tank
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the surge tank pressure
cap, is hot. Wait for the cooling system and surge
tank pressure cap to cool if you ever have to turn
the pressure cap.
If coolant is needed, add the proper DEX-COOL
®
coolant mixture at the coolant surge tank.If no coolant is visible in the surge tank, add coolant as
follows:
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 turn and then stop.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap slowly and
remove it.
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3. Fill the coolant surge tank with the proper mixture,
to slightly above the FROID/FULL COLD line on the
side 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. The upper radiator
hose is the top hose coming out of the radiator, on
the passenger side of the vehicle. 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 FROID/FULL COLD
line on the side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Recheck the coolant level in the bottle next time you
use your vehicle to insure the system is full when cold.
SeeEngine Coolant on page 5-32.
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Checking Coolant in the Intercooler
System (CTS-V)
The vehicle must be on a level surface when checking
the coolant level.
The super charged engine intercooler coolant ll bottle
is located in the engine compartment on the passenger
side of the vehicle. SeeEngine Compartment
Overview on page 5-14.
Check to see if coolant is visible in the coolant ll bottle.
If the coolant inside the coolant ll bottle 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 COLD FILL
mark, add a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant at the coolant ll bottle, but be sure
the cooling system is cool before this is done.
If the engine is warm or hot, the coolant level should be
at or above the COLD FILL line on the side of the coolant
ll bottle. If the engine is cold, the coolant level should be
near the COLD FILL line on the side of the coolant ll
bottle. If it is not, you could have a leak in the cooling
system.
Adding Coolant to the Intercooler
System Coolant (CTS-V)
1. Remove the intercooler system pressure cap when
the intercooler system hoses are 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 allows any pressure still left
to be vented.
2. Then keep turning the pressure cap slowly and
remove it.
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If you do decide to lift the hood, make sure the vehicle
is parked on a level surface.
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run
the engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:If the engine catches re while driving with
no coolant, the vehicle can be badly damaged.
The costly repairs would not be covered by
the vehicle warranty. SeeOverheated Engine
Protection Operating Mode on page 5-39for
information on driving to a safe place in an
emergency.If Steam Is Coming From The Engine
Compartment
{CAUTION:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no sign
of steam or coolant before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch re. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 5-39for information on driving to a safe
place in an emergency.
5-38

Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous. It
could affect the braking and handling of your
vehicle, make your tires lose air and make you lose
control. You could have a collision in which you or
others could be injured. Always use the correct
wheel, wheel bolts, and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire clearance to
the body and chassis.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause a crash. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the
vehicle. In an emergency, you can use a
cloth or a paper towel to do this; but be sure
to use a scraper or wire brush later, if you
need to, to get all the rust or dirt off.
{CAUTION:
Never use oil or grease on studs or the threads of
the wheel nuts. If you do, the wheel nuts might
come loose and the wheel could fall off, causing
a crash.
5-83