I was backing my car into my drive way and I put it in park. When I put it back in drive it cut off. I didn't turn the car off anytime when I backed it up and put in park. When it cut off the battery light came on. So I checked the battery with a multimeter and read 12vdc so it's good. So I tried to start it several times, it would start for about 3 to 7 seconds then cut off and each time the battery light comes on. What could be the problem?