Check out this document...it has all the details on TPMS operation:
http://prodcds.bmwuniversity.com/lib...nd%20Tires.pdf

In the 2008 5353xi, there is one antenna for all the wheel sensors. But, rotating the tires does not require any coding to detect the new wheel sensor location. See page 26:

"Electronic assignment of the wheel electronic modules is not carried out until movement
is detected. This is to avoid any signals from vehicles in close proximity. Especially
vehicles which are equipped with similar TPM systems.

Data is transmitted to the central receiving antenna via a transmit stage in the wheel
transmitter module. The module at each wheel has an individual identifier (ID) which
is also transmitted every time data is transmitted."

 

Thanks for the document and info.. I really appreciate it! Although it doesn't explain to me how it got the tire wrong if it retransmits the tire location etc upon relearn. We'll see next time it gives me a warning when it gets cold again.. I'll check before the tires warm up so I know if it got the location wrong again.