Hi all,

I have a new VRS with TPM, I have a good set of Audi wheels and tyres that fit ok, my question is how does the TPM work and what happens when you change the wheels. Can it be turned off.

Just reset it when you have fitted new wheels and are happy pressures are correct

Only guessing it's passive like on many Audis and triggers if there is a change in circumference (measured by ABS system?) compared to its set point. When temperature drops, all pressures drop too, but I've not noticed it trigger, maybe because I check regularly out of habit.

Don't rely on it in place of these checks, but it should alert you to a puncture.

Don't forget to reset periodically and after any change.

Edited 4 October, 201510 yr by Jeeves

OK. A convenient experiment with my Audi today.

 

I fitted some 18" wheels which had the same 245/45 R 18 offroad tyres I used with my Scout, so they're a bit too small.  There's a reason and more to it than that, but,,,,

 

Anyway, after inflating correctly I didn't reset the TPMS and got no warning either.

 

It's clearly a difference compared to one or more other tyres which triggers it, explaining why a temperature induced pressure drop doesn't. i.e. it's basic and doesn't negate regular checks.

Thanks for the replies, sounds like the abs measurement sounds right. I know some manufacturers use things inside the rims some times on the valves.

I will see what happens when I put the winters on.

As said above, the TPMS works from the ABS sensors. So if one of the wheels looses pressure the system picks it up as being different. You could start with all four wheels being different, and reset the the system, it'd be happy!

 

When you fit your winter wheels/tyres, make sure you are happy with the pressure and reset the TPMS before you set off.

See here in an old tech thread I started way back...............

 

http://www.briskoda.net/forums/topic/214776-wtf-is-abs-edl-asr-esp-hhcetc/