2005 CADILLAC CTS V cooling

A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-96.
B. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-37.
C. Battery. SeeBattery on page 5-41.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-16.
E. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-16.
F. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-36.G. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-38.
H. Hydraulic Clutch Reservoir. See “When to Check
and What to Use” underHydraulic Clutch on
page 5-25.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-28
andCooling System on page 5-31.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-21.
5-15

Hydraulic Clutch
It is not necessary to regularly check clutch uid
unless you suspect there is a leak in the system.
Adding uid will not correct a leak.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
The hydraulic clutch uid
reservoir cap has this
symbol on it. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.
Refer to the Maintenance Schedule to determine how
often you should check the uid level in your clutch
master cylinder reservoir and for the proper uid to use.
SeeOwner Checks and Services on page 6-9and
Recommended Fluids and Lubricants on page 6-12.
How to Check and Add Fluid
Make sure the uid level is at the MIN line on the side
of the reservoir. If it is not, remove the cap and add
the proper uid until the level reaches the MIN line.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating, seeEngine Overheating
on page 5-28.
5-25

A 50/50 mixture of clean, drinkable water and
DEX-COOL®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®coolant which will not damage
aluminum parts. If you use this coolant mixture, you
do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:If you use an improper coolant mixture, your
engine could overheat and be badly damaged. The
repair cost would not be covered by your warranty.
Too much water in the mixture can freeze and crack
the engine, radiator, heater core and other parts.
If you have to add coolant more than once or twice a
year, have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-26

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank and Pressure Cap
B. Electric Engine Cooling Fans{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If the coolant inside the coolant surge tank is boiling,
do not do anything else until it cools down. The vehicle
should be parked on a level surface.
3.6L V6 engine shown, 2.8L V6 and 5.7L V8
engines similar
5-31

If the engine is warm or hot, the coolant level should be
at or above the FULL COLD/FROID line on the side
of the coolant surge tank. If the engine is cold, the
coolant level should be near the FULL COLD/FROID
line on the side of the coolant surge tank. If it is not, you
may have a leak at the pressure cap or in the radiator
hoses, heater hoses, radiator, water pump or
somewhere else in the cooling system.
{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.If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-30for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-32

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at the FULL COLD/FROID
line on the side of the coolant surge tank, add a
50/50 mixture ofclean, drinkable waterand 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. SeeEngine
Coolant on page 5-25for more information.
{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 coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
5-33

{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.
If no coolant is visible in the surge tank, add coolant as
follows:
1. You can 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 (left) 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.
5-34

3. Fill the coolant surge tank with the proper mixture,
to slightly above the FULL COLD/FROID 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’s 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 FULL COLD/FROID
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.
Start the engine and allow it to warm up. If the
Check Coolant Level message does not appear on
the Driver Information Center (DIC), the coolant is at
the proper ll level. If a Check Coolant Level message
does appear, repeat Steps 1 to 3 then reinstall the
pressure cap, or see your dealer.
5-35