Cadillac 2005 STS - Manual (Page 315)

Checking Coolant
The coolant surge tank and pressure cap are located on
the driver’s side of the vehicle, toward the rear of the
engine compartment. See Engine Compartment
Overview on page 5-12 for more information on location.
{ CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD/FROID line on the side of the surge tank.
Follow the arrow from the top of the tank down the side
to the horizontal mark.
If the Check Coolant Level message in the Driver
Information Center (DIC) comes on and stays on, it
means you are low on engine coolant. See DIC
Warnings and Messages on page 3-74 for more
information.
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