Almc230

Hello all. my wife and I recently purchased a 2005 Audi a6 with push button start and stop. However, 4 months after we bought the car the start button is not engaging. Now since that isn't working the trunk wont close at times, the front pass window is inop from the drivers side. Have we bought a lemon that only has 64k miles? I need some advise to help me diagnose the problems. I will buy the parts and fix the car myself. Recently, the last time the car has been worked on was from the dealer to do the cam open campaign.