Is there a safety switch to turn motor off if over heating

What is your question?

Vehicle over heated and won't start. I checked compression and 2 have 185lbs and 4 of them have 0. The vehicle was losing coolant. Is there something else it could be other then motor blown.

What makes this problem better or worse?

Vehicle won't start

How long has your 2005 Porsche Boxster had this problem?

Few days