1989 Mercedes-Benz Mercedes Benz 500 Class "becker grand prix car radio" Questions

Becker Grand Prix 2000 radio with RDS MODEL 208 with CODE (510) MB Exquisit radio with traffic news decoder, with RDS (Becker) with CODE (512) MB Special radio with traffic news decoder, with RDS with

Becker Grand Prix 2000 with RDS) If the radio is disconnected from the power supply, it is not operational when re-connected. After switching on the ignition and the radio, the readout CODE appears in