2012 passat wont switch off. I changed a fuse yesterday, now I can turn my car to the off position, take my key out , and it still running. Is there any one out here who can help me out.

which fuse did you change? my advice to you is to take your automobile to your local shop and a qualified technician should be able to diagnose the malfunctioning automobile

Does the engine "run on" after key off . This could possibly be due to fuel quality/detonation . This is either a fuel issue of Engine Control Module dysfunction . Try a tankful of QUALITY , premium grade fuel before you panic out . If you have not received a check engine light it is most probably due to low quality low octane fuel . If the engine runs normally with the key out , you possibly have a failed ignition switch . Check for recalls or dealer service bulletins before you spend a lot of money on this . VW is notorious for not advising customers of ( secret recalls) or dealer service advisories . I say this after owning three ( never again ! )

OK thanks you for your solutions. I think I have the problem under hand. I change what I belive was the dashboard/ or fuel filter fuse, my brother-in-law put a 15 fuse in a 10 fuse slot. I believe he shot the fuse slot. I change another fuse that was blown, and now everything is back to normal. The only thing different is the first fuse we change is no longer needed. I don't even have it in and everything is running fine. I still plan to take it to the dealership either way.

word to the wise amigo . Until you resolve the original issue . Considering your have replaced a smaller capacity fuse with a larger one ........... keep a fire extinguisher HANDY in your vehicle .