Agreed

Gilly,

I guess I'm confused about the communications the key, or the car initiates, and how whatever data is stored in the key gets delivered to the car. Can you elaborate about a little bit on the front end of that communication?

Thanks.

The transponders in the key work without batteries. Similar to the "Speedpass" things you can "wave" at the gas pumps to charge for gas. Inserting the key powers the transponders inductively. There are 2 transponders, a fixed and a rolling code. The "fixed" code identifies the key to the vehicle as being correct. The rolling code, sort of like a automatic garage door opener, is a security code which changes after the key is used, different every time. Every key has 200,000 rolling codes. If it ever manages to work that long, it won't work after 200,000 starts. Each key can be replaced twice. You can have up to 8 keys at a time. This gives a total of 24 keys, but again you can only have 8 at the same time, not all 24, at least not that would all work. Enough details?
Gilly

Just about perfect! ;)

Thanks Gilly, very informative.