how great. i changed my batteries and still nothing. how do i synchronize it?? and i have an older remote and this one tech said you need a new egnition and it costs around 600 and with labor around a 1000 bucks.The problem was very simple. The previous owner had the batteries in wrong (in both keys). He had the car for five years so I assumed he knew. I changed the batteries and put them in the right way and both keys now work. It is amazing, how after ten years, the keys work so well and it operates the doors, as well and the windows and sun roof. I'm glad I did not have to buy new keys, just new batteries!