Originally Posted by tom2112
You know, I read that whole thing from the BenzWorld forum, and one thing doesn't add up:
An RFID chip is pre-programmed, and it would have to be pre-programmed before it was inserted in the fob. If so, then the actual programmable part of the RFID process is in the car - not the fob. Which is why you can program a brand new key to work with your car - all by yourself - with the method posted above.
The car doesn't program the RFID in the fob, it reads it and puts it into it's own "accept" list.
So, why is it that we can't make the ebay key fobs work? Hmmm...
It's my understanding that when you order a replacement key from the factory, they program the RFID chip via your VIN. I suspect there may be a small number of RFID codes; you just have to have the right one with your key.
With the correct code, your car accepts the key; without it, it will not. The programming you do with your car for a new fob does not affect nor relate to the RFID, but merely enables the car to respond to the lock/unlock commands from the fob.
At least that is my understanding. This still means any fob but one pre-programmed to your VIN will not work nor is programmable by you to work.
