hi new here i have a l322 03 plate and today i disconnected my amp for my stereo system and by mistake wen putting back put positive to negative and vise verser and after that the tailgate button does not work and neither does the cigarette sockets and when tried driving it would not go faster than 25mph now it will not even start i have checked all fuses and cant find a solution please help me somebody .... i have checked all fuses . any help would be fantastic thanks ...