"Installing a hitch" meaning what? setting up the draw bar on an existing installation, or a complete installation of drawbar and light control box from scratch?.
If from scratch then I believe that the factory trailer light interface box will disable the rear PDC sensors. I am not sure if permanent or not.
I have aftermarket interface unit that does NOT disable the rear PDC and it is a pain - when the tow ball is installed (not even a trailer connected) the PDC goes off as soon as reverse is selected so disabling is good IMO.
VW Touareg V6 TDI 4Motion with a smooth as AISIN 8 speed auto gearbox that WORKS!
X3 3.0d 2006 (MY07) sold