Tpms identification

[SteBrown91]

Hi,

I am watching some winter wheels on eBay, and I asked the seller if they have the tpms sensors.

He has replied it has sensors (the wheels were new from bmw last year) but his car is the older style where it only detects pressure loss. Do the newer style sensors work with the older style system? And is there any way to tell between the two types visually (without taking the tyres off)

Thanks

[AlwynMike]

The two types are mutually exclusive.
The old type have no sensors, and are identifiable by using ordinary, old fashioned valves, which may or may not just be black rubber.
The old type that just detects loss works with the ABS sensors to detect a change in circumference of the tyre when it goes down (the tyre radius reduces with lack of air pressure which the ABS detects as a change in wheel speed.
The newer type TPMS generally have larger silver valves that transmit the pressure and temperature values to the car for display in idrive.

[SteBrown91]

Cheers it does have the metal valve stems so bought them and will pick them up when back off holiday