Surface pre-treatment
WARNING: This page is about a different car, the 2011 BMW 750xi, 2011 BMW 750Lxi, 2010 BMW 750xi, and 2010 BMW 750Lxi. However, it is still accessible from the selected car via links, so may be relevant.
Grind surface to a metallic bright-finish. The surface must be clean, dry and free from grease.
Clean the surface with a cleaning agent R1 and let it vent for 2-3 minutes.