Cadillac 2010 STS Owner's Manual

Also see for 2010 STS: Brochure Owner's manual

How to Add Coolant to the Surge Tank{ WARNING:You can be burned if you spill coolant on hotengine parts. Coolant contains ethylene glycoland 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 coolingsystem can blow out and burn you badly. They areunder pressure, and if you turn the coolant surgetank pressure cap — even a little — they can comeout at high speed. Never turn the cap when thecooling system, including the coolant surge tankpressure cap, is hot. Wait for the cooling systemand coolant surge tank pressure cap to cool if youever have to turn the pressure cap.{ WARNING:An electric engine cooling fan under the hood canstart up even when the engine is not running andcan cause injury. Keep hands, clothing, and toolsaway from any underhood electric fan.If no coolant is visible in the surge tank, add coolant asfollows:1. Remove the coolant surge tank pressure cap whenthe cooling system, including the coolant surgetank pressure cap and upper radiator hose,is no longer hot. Turn the pressure cap slowlycounterclockwise about one-quarter of a turn.If you hear a hiss, wait for that to stop. A hissmeans there is still some pressure left.6-30