I have a 2002 rt10. Every now and then ( happened twice) I get into the car, put the key in the ignition and the doors lock, alarm goes off and car will not start. I get out disconnect the battery, let it sit for moment hook up the battery then hold both the buttons on the FOB and the car goes back to normal.I checked the status of the battery and it was at full charge. 13.0.Question: what causes the alarm to go off by itself? I rarely lock the car.