You are guys assuming that this will immediately result in killing the wallet. When I had X5 35d they had to do diagnosis using engineers from Munich. Engineers from Munich were instructing technicians here what to do. This being vehicle with 1st gen SCR system, it was hard to identify what was the cause of high NOx, NOx sensors itself, DEF injector, or catalytic mixer. In the end, it was a mixer, and being out of warranty I had to pay that, but everything else engineers from Munich told technicians here to change when they were chasing issues, was on BMW.