Gearbox position sensor

[Monty84]

My gearbox position sensor seems to be a little temperamental, most of the time it's right as rain, but usually when left for sometime when cold it seems to loose its position, as in no reading on dash.  Can anybody inform me of the location of the position switch and is it something I can replace or contacts I can clean up?

[kkx5]

http://www.realoem.com/bmw/showparts.do ... g=25&fg=20