This is sounds the same as the problem that I had with my SCREEM. 3 second run, then stop, then nothing---disconnect battery and 3 more times. If you research and this is it, you have 30 total tries and the ECM with stop working. There is a program in it that thinks that you are trying to steal the car and will kill the ECM---forever. The dealer HAD to but me one because I showed them what I found and MADE them put this on the work order. Well, the tech went over 30 tries and the ECM was cooked. Good luck. Jimmy