Black plate (19,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
6014430) - 2014 - 2nd Edition - 8/23/13
Vehicle Care 10-19
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.
{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.(Continued)
Warning (Continued)
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.
{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 tankpressure cap from the top
chamber when the cooling
system, including the coolant
Black plate (20,1)Cadillac ATS Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
6014430) - 2014 - 2nd Edition - 8/23/13
10-20 Vehicle Care
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
3. Fill the surge tank top chamber with 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 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. See
Roadside Service on page 13-5.
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.
