I have a low mileage 2003 C70 Convertible. Recently it has developed an intermittent fault which is driving me nuts. The roof control button starts to flash and an audible (bleeping) alarm goes off. The rear heated window will not operate. ( but I assume this is normal if the roof is opened) If I push the roof button (rocker switch) in any direction the roof will open. This will not necessarily stop the alarm going off. As I said it is an intermittent fault. I have had the micro switches checked out and they all seem to be working properly. ANY IDEAS ???