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Black plate (25,1)Cadillac STS Owner Manual - 2011
{WARNING:
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 fire, and you could be burned.
Get any leak fixed 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 50 000 km (30,000 miles)
or 24 months, whichever occurs first. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL (silicate-free) coolant in the
vehicle.
Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to remain in the vehicle for five years or 240 000 km
(150,000 miles), whichever occurs first.
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 on page 6‑30
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Black plate (26,1)Cadillac STS Owner Manual - 2011
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, 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 fire 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.
See Recommended Fluids and Lubricants
on
page 7‑9for more information.
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Black plate (28,1)Cadillac STS Owner Manual - 2011
How to Add Coolant to the Surge Tank
{WARNING:
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.
{WARNING:
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.
{WARNING:
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.
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 of a turn.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
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Black plate (30,1)Cadillac STS Owner Manual - 2011
4. With the coolant surge tank pressure cap off, startthe engine and let it run until you can feel the
upper radiator hose getting hot. The upper radiator
hose is the largest of the hoses which comes 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 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.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There are two engine hot messages that could be
displayed in the Driver Information Center (DIC). See
DIC Warnings and Messages
on page 4‑76DIC
Warnings and Messages for more information. If the engine is overheating, then you will find a coolant
temperature gauge and a coolant warning light on the
instrument panel. See
Engine Coolant Temperature
Gauge
on page 4‑61and Engine Coolant Temperature
Warning Lighton page 4‑61for more information.
You may decide not to lift the hood when this warning
appears, but instead get service help right away. See
Roadside Service on page 8‑8.
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 your engine
without coolant is not covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode for information on driving to a safe
place in an emergency.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑32for information on
driving to a safe place in an emergency.
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