When iplug my charger in my car the picture disappears but you can hear it when i unplug it the picture comes back

I believe what is happening, is there is a short internally in the unit where the 12 volt connection plugs in. If you plug it in goes out, then unplug it goes back lit, then there is a short, Here is a couple things to try, to confirm area of problem. Take your unit, and try plugging it in another car, if does the same thing, then it your unit most likely, or could be your 12 volt charger. Here is last test to confirm. Yes it is possible it could be the charger it self. Try picking up a new charger, save receipt , so can take back, try new charger with unit and plug back in your car. This way you have now determined if it unit, charger or car 12 volt female in. Please if this has helped you, please don't forget to give me the thumbs up to help me and others. Thanks, mike from fixya