Hello to all! Constantly lurking but not really writing much on the forum.

I'm having a very strange issue lately with the ABS/DSC based TMPS on my Clubby. I had a valve which was constantly leaking some pressure and I found that I had no warning about it, while I had in the past with another set of valves (yes, I've been quite unfortunate with valves, it appears..)

To better explain the behaviour, I'll say this: each time I found (because of the car dynamics or visually) that the tire was under-inflated, I restored the correct pressure and reset the TPMS system. Later on, I experienced again no warning when the tire was under-inflated again. The only moment in which I got the indication was whenever I inflated the tire AND forgot to reset the system. In that moment I had all of the tire inflated at the same pressure plus having the TMPS warning. I understand that it was detecting a different rotation speed on that particular wheel, but why should it be indicating when everything’s ok and not when the tire is constantly losing pressure? No matter what the residual pressure I detected (say, 1.8 bars, 1.6…) as soon as I restored the target 2.2 and forgot to reset, I had the warning.

Could it be because the leaking was so slow that the TMPS never managed to calibrate properly, and the inflating, on the other hand, caused and abrupt decrease in the wheel rotation frequency?

Had anyone experienced such an issue in the past?

Could another TMPS system (the one with sensors) be installed and reprogrammed on this model, or should I rely on the aftermarket solutions?

 

Hello - I'm assuming you have the TMPS system that uses the ABS to monitor wheel speed and not the later version that has the sensors built into the wheel valves? (Not sure as I had thought that all the US spec R55 had the later system but your last line in your post suggests not).

Anyways - we have a 2008 R55 in the UK and it will display the same symptoms as yours - one tyre/rim has a slow leak and will drop from 34 psi to 20/22 psi over maybe 6 weeks or so - no warnings on the dash etc etc. If I reinflate that one back to 34 psi from about 20/22 then I will get the warning if I do not reset. If I reinflate at a shorter internal (say 30psi) then I never have to reset.

My take is like yours i.e. that the ABS based system misses a very slow leak - we live with it and just check the tyres manually.

 

Your assumption is correct: I don't live in the US (I'm Italian) and I have a 2008 R55 which TPMS is based on the ABS reading.
Thank you very much for the reply, I assume it is related to the way the system works and I (we) will have to live with it!

 

The TPMS using the ABS will detect it very late, like you've suggested.

It'll cost a lot money to get the OE TPMS sensors installed and coded in.

Cheapest is to go aftermarket external/internal bluetooth TPMS sensors, although the external version the cap sensors are chunkier than normal but you'll always have a display of all tyre pressure when you get in the car.

 

Oops - my bad, despite being in the EU I always assume everybody else on here is in the US - apologies!

 

No worries!!

 

I hate the idea of having a device as ugly as those proprietary interfaces on my dash. Given I have a phone always on the car (in a Cravenspeed scissor holder) I was in fact searching for Bluetooth external sensors, but didn't manage to find any set which was connectable to the phone and be visible on, say, Torque or other apps.
Do you happen to know one?

 

I prefer the solar powered ugly proprietary interfaces on the dash myself .

Should be loads on ebay, Amazon, AliExpress etc...

https://www.ebay.com/sch/i.html?_fro...s+app&_sacat=0