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Cadillac ATS/ATS-V Owner Manual (GMNA-Localizing-MidEast-10287885) -
2017 - crc - 6/16/16
248 VEHICLE CARE
{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.
Caution
Using coolant other than
DEX-COOL®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant could require changing
sooner. Any repairs would not be
covered by the vehicle warranty.
Always use DEX-COOL (silicate-free)
coolant in the vehicle.
Cooling System
(Intercooler)
Intercooler ATS-V Only
The 3.6L V6 twin turbo engine (LF4)
has an intercooler cooling system.
The intercooler cooling system has a
special procedure for draining and
adding coolant. Because this
procedure is difficult, see the dealer
for service if the intercooler is low on
coolant or a leak is suspected.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine coolant.
See Maintenance Schedule 0307 and
Recommended Fluids and
Lubricants 0314.
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 0251.
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
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. This mixture:
. Gives freezing protection down to
−37 °C (−34 °F), outside
temperature.
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Cadillac ATS/ATS-V Owner Manual (GMNA-Localizing-MidEast-10287885) -
2017 - crc - 6/16/16
250 VEHICLE CARE
be sure the cooling system, including
the coolant surge tank pressure cap, is
cool before you do it.
{Warning
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. 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.
{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
coolant warning system is set for
the proper coolant mixture. With
plain water or the wrong mixture,
the engine could get too hot but(Continued)
Warning (Continued)
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.
Caution
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.
{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. 1. Remove the coolant surge tank
pressure 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
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Cadillac ATS/ATS-V Owner Manual (GMNA-Localizing-MidEast-10287885) -
2017 - crc - 6/16/16
VEHICLE CARE 251
3. Fill the surge tank top chamberwith the proper DEX-COOL
coolant 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. 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 DEX-COOL coolant
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.Caution
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.
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 1-3 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.
Engine Overheating
The vehicle has several indicators to
warn of the engine overheating.
There is an engine coolant
temperature gauge and an engine
coolant temperature warning light on
the instrument cluster. See Engine
Coolant Temperature Gauge 0111 and
Engine Coolant Temperature Warning
Light 0119. The vehicle may also
display a message on the Driver
Information Center (DIC). See Engine
Cooling System Messages 0129.
If the decision is made not to lift the
hood when this warning appears, get
service help right away.
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.