What does code P0600 mean?

On modern vehicles there are many control modules on different networks (CAN,MOST, VAN, LIN, D2B etc...) Could be a communication problem between modules on one of the network. It would be better to have the OE BMW code, instead of the OBDII because it's more specific. These type of codes are common if the battery goes down and modules lose power, however it can be a real network problem, which needs further diagnostics. There is a big possibility for other comm. codes in other modules, i.e. if there is a comm. problem between the DME (engine control) and EGS (transmission) the comm. codes will be registered in both - therefor both needs to be reset. Zee