Technical Service Bulletin B511318 — 2020 BMW Z4

LIN BUS FAULTS WITH EXTERIOR REARVIEW MIRROR GLASS DAMAGE: Any or all of these conditions may be present: A. The exterior rearview mirror glass is discolored or cracked B. The power windows and folding mirrors may not operate C. One or more of the following LIN bus faults are stored in the BDC (Body Domain Controller): D90C03 LIN bus master B: short circuit - BDC D90C04 LIN bus master B: No communication - BDC D90C05 LIN bus master B: Communication failed - BDC D90D07 Operating facility switch block (LIN): Missing LIN slave D90D0A exterior rearview mirror left (LIN bus): Absent LIN slave - BDC D90D0D exterior rearview mirror right (LIN bus): Absent LIN slave - BDC 804246 exterior rearview mirror left (LIN bus): Heating or electrochrome: faulty - BDC 804256 exterior rearview mirror right (LIN bus): Heating or electrochrome: faulty - BDC 804265 exterior mirror left or right: Excess temperature - BDC 804260 exterior mirror left or right: Overvoltage - BDC 804261 exterior mirror left or right: Undervoltage - BDC Faulty exterior rearview mirror electronics have created a short on the LIN bus damaging the mirror glass and causing functional errors in power window and exterior mirror operation.