I have a P85D and I can't open the door or start the car when the keyfob has no batteries or has dead batteries. I read in the manual that I could put it on the passenger side windshield to open the door. I also read that you could put the key in the cup holder or near the charge port to start the car. Neither of these features worked for me. I am worried that one day my batteries would die and I'd be stuck in the middle of nowhere. Has anyone successfully opened their doors/start their car with the battery out of their keyfobs?