if the x3 has the same or similar heater valve take a look at my temporary/permanent fix

http://www.xoutpost.com/bmw-sav-foru...-temp-fix.html


looking at the realeom it looks to be the same just a single not double like in e53s.

you can test it by taking a 12v batter and touching the terminals you should see a +/- so its not hard to do. if there is not movement there is a link on my diy that some guy did. he foudn that the terminal wire had corroded away and all you had to do was solder a bit on and bam its good as new!!!