"the-man-himself" > wrote in message
...
>> hey guys .new rules came out on this.
>> anyone know BMW's plans for it ???
>> who will provide these devices to BMW ??
>>
> in uk bmw has a tyre pressure monitoring system it uses the abs to detect
> if one wheel is turning faster than the other so detecting pressure drop
> i.e. a flat tyre produces a smaller diameter wheel and so turns faster
> hope this helps
>
>
E38 7 series had transponders in the wheels - they had to be replaced
when batteries go flat.