Before you can use a calculator, you need the unique 14-digit serial number of your radio.

Valid serials often start with BP , C7 , CM , GM , VWZ , or AUZ followed by a string of numbers (e.g., BP026318472532).

How to find your car radio code and unlock your stereo - RAC

If you’ve recently changed your car battery or had a service that required disconnecting power, you’ve likely encountered the frustrating or "CODE" message on your dashboard. This anti-theft feature is standard for Blaupunkt units, but you don't need to visit a dealership and pay a hefty fee to fix it.