That is a great post! Thank you! However, I disagree on one small point, although it is moot to the person asking questions about pairing the DME and EWS. The directions on the net regarding how one pairs the *remote* section of a key (i.e. not the transponder) to a car are downright misleading and wrong. Generally, they describe a sequence of lock/unlock sessions after having turned the ignition on/off within 5 seconds (or some variant thereof). Those directions do not pair the remote to the DME, they resynchronize a key that has been previously paired. A rolling code is used to ensure that a remote cannot be easily compromised. However, the remote and its seed must first be paired using DIS. This is where the barcode information that comes with a brand new remote come into play. Unfortunately, that data is generally lost and 99.9% of the keys sold on eBay do *not* have that information. Sadly, that effectively means the keys are useless. However, another member reversed engineered the algorithm (it was actually pretty simplistic) from the data provided on the label affixed to the remote's circuit board. You simply *must* use this algorithm to generate the data and input that date using DIS. Until you do that, it is not possible to pair a remote the the DME.
Now, in fairness, this absurd approach was done away with, I believe, in later model Minis. Given that Mini is owned by BMW and shares many of the same components, it is likely that later model BMWs also have a simplified (i.e. no need to use DIS) approach wherein the internet style directions do work. If I remember correctly, on the Mini line, that change was made in 2004 or 2005.
Also, the transponder has more than EEPROM in it (or, at least, it acts as such). Once the VIN is programmed into it, that data cannot be changed. Whether this is through an internal protection device or because it is PROM instead of EEPROM, I do not know. In truth, it doesn't really matter though, other than to say that you cannot reuse a transponder chip. :-( As a matter of conversation, I do know that the transponder keeps track of the mileage on the car. So, clearly there is a back path where the ring is being used to write to the transponder, not just read from it. However, that still doesn't mean it is EEPROM. It is possible, although not likely, that they are only writing new data. All of this could be confirmed by looking at the datasheet which I have somewhere in my computer. Anyhow, it makes for an interesting theoretical conversation but there really isn't much practical use in knowing that I can think of.
One last thing.... Although 10 slots are available for transponder (so 10 keys can be supported), on the 2002 Mini, only 4 slots for remotes are available within the DME. That is just a quick FYI for someone reading this years down the road...
Last edited by MiniCooper2002; 06-07-2013 at 12:31 AM.