My 05 bmw 645 is saying transmission gear failure

This warning light and preventing the starting of the vehicle is possibly due to an electronic concern which prevents starting the vehicle because information about the transmission gear selector being in "park" or "neutral" is not present. Why this is the case will need to be checked out via troubleshooting. The engine is also inhibited if starting the engine and running the vehicle can cause damage or trouble within the transmission due to an existing problem. In either case, it's impossible to know the root cause without hands on testing, which is why there is no easier recommendation to give you in answering your question. www.repairpal.com/repair-shops