It is really unbelievable story,but for the life of me I cannot find the drive blet routing diagram for this engine.The other models equipped with N52q engine have only 1 drive belt and only X5 has 2 belts,1 small is for the AC compressor.Every diagram that i found,including all BMW documentation,has the single belt layout shown.
If someone with this engine in his X5 can snap a quick photo,or knows about a belt diagram,this help will be highly appreciated.