What does the ford f150 engine coolant over temperature mean?

The engine coolant over temperature error message on a Ford F-150 likely is indicative of a faulty sensor, though it's very possible that Your coolant actually is over temperature. In the latter case, You can try any of these things to temporarily remedy it until You can address the coolant issue (likely, You need to top off Your radiator): Turn off the air conditioner, if You have it running; the A/C puts a heavy load on Your engine. Turn ON the heater; this serves to blow some of that excess heat into the cabin; You'll be uncomfortable, but Your expensive engine will let You limp home. Not helping Then try parking Your car and revving the engine, to let the radiator fan do some of the work --- as well as popping Your hood.