It sounds like you've both got a coded sound system that has had the incorrect code entered too many times, at a guess any more than three attempts locks your system. This will need the pro's to unlock, but this will probably be cheaper than a replacement system. Most aftermarket systems will need a "connect 2" adapter or similar to allow you to use your steering wheel controls . Another option is to check your friendly Ebay for an unlocked standard stereo which will not need a code, or a standard kit with its own code, check on youtube on how to enter the code, remember three attempts. codes are normally with your hand book set, and are often tipexed on the stereo's casing. Good luck!