Odd one for you, over the last 2 days my 320ci has had the aux fan kick in when i start the car?
This has only happened on the last 2 days when the outside temp is 0 or below degrees? It will run the whole time on my journey to work, switch off when you shut off the engine, but when i start the car at lunch the aux fan doesnt kick in at all?
I would have said a relay fault if the fan kicks in all the time when the car is running, but as it only does it when the temp is cold it confuses me?
If i switch aircon on it comes on fine too so im guessing no power issues either.
Could it be connected to the ext temp sensor in any way at all? Or maybe a coolant sensor?
It done this one day last year, but hasnt happened since then.....