I have just put a deposit down on a 2003 634SE Mercedes 2.7 Auto . I am due to pick it up next week after it has been MOT'd and serviced. At the time of purchasing and trying out the van, I noticed that the demister fan was not coming on, and the salesman has told me that it does not come on because it works in conjunction with climate control. Does anyone know if this is correct?. I would have thought the fan needed to work to clear the windscreenif nothing else.