Let me start out and say that the drivers door was replaced years ago. And the actual physical key never worked in the new door. Only the fob would unlock the car.we just replaced the key fob battery. And the fob no longer works. Placed the old battery back in but still nothing. So I read up on this and it might need to be reprogrammed. But I'm locked out so I can't do that yet. But more still, there was some talk of an immobilizer unit which can only be reprogrammed at a dealer. So my question is if I can get into my car and reprogram the key fob will everything be ok? Or should I be calling to get towed to a dealership.