Hi I bought a 2005 c200 cdi coupe diesel automatic, a few weeks ago but when i turn it to position 2 to let the preglow light heat, it goes out then as soon as i start to drive it comes back on for a few minutes. it only started doing it last week but i thought it was because i was in the country and the damp was affecting it but im home now and its still doing it. Help would be greatly appreciated. I lovde this car and hope i havnt bought a dud.