I have purchased five of these passenger cars recently. I cannot get the magnet activated interior lights to work. Yes, I have removed the plastic strip from the ends of the cars. Yes, I have verified the plastic strip was completely removed from the battery and did not tear. Yes, I have completely disassembled the cars and verified the battery is there. Yes, I am placing the magnet over the correct end of the car. Does anyone have an insight to what is going on?