Excessive Radiator Fluid Temp & Air con temp issue
Hello there - whilst driving on the motorway today in my 159 d, i got an instrument dash alert, "Excessive Radiator Fluid Temp - stop and turn off engine." I pulled into the hard shoulder, turned the engine off, popped the bonnet and all seemed normal (no steam/hissing/un wanted noise etc) I sat there for 5 mins wondering what to do - i turned the engine over and the water temp gauge dropped back to 90 so off i went again - this actually happened about 5 times during my journey, i was ok at maintaining 90 oC when driving at 60mph.
I also noted that no heat at all, just cool air was available from the air con / heater vents in the cabin.
Are they related?
An thoughts on what the issue(s) might be?