Basic tyre pressure system reporting the position of the problematic tyre - Interesting discovery for me

[serdar_18fr]

No pressure sensors in the tyres, just basic ABS speed sensors, measuring the rotation. I always thought it could only report that there's a problem with pressures, not the position of the deflated tyre.

After switching to summer tyres yesterday afternoon, system reported a pressure loss this morning "on front left tyre" - to my surprise.

In my old car (A 2007 Opel Corsa Sport) it was working like I said above, reporting the problem as a general warning only. Now I see that this basic system is developed a step further. That's nice, I guess.

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[Walone]

No pressure sensors in the tyres, just basic ABS speed sensors, measuring the rotation. I always thought it could only report that there's a problem with pressures, not the position of the deflated tyre.

After switching to summer tyres yesterday afternoon, system reported a pressure loss this morning "on front left tyre" - to my surprise.

In my old car (A 2007 Opel Corsa Sport) it was working like I said above, reporting the problem as a general warning only. Now I see that this basic system is developed a step further. That's nice, I guess.

Sent from my 23013PC75G using Tapatalk

Out of interest, what was the difference in the tyre pressures? When I did a test on my car a few years ago, I had to lower the pressure on one tyre by 8psi before it showed an error.

 

[serdar_18fr]

Out of interest, what was the difference in the tyre pressures? When I did a test on my car a few years ago, I had to lower the pressure on one tyre by 8psi before it showed an error.

The last time I had reset the system was right after I switched to winter tyres in November I guess, and I had told the employee at the tyre shop to set the pressures to 34/32 f/r. So it means I didn't check them in last five months. While switching to summers yesterday I told them to set the pressures, to 32/30. After I got the warning, I checked them and they were more or less correct at 32/30 (not sure how precise my Michelin digital gauge is). So the difference triggered the warning looks like 2 psi. But it is strange why the warning was for front left only and not for others and also not sure if it's possible for a tyre to keep its pressure for five months.

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[Walone]

The last time I had reset the system was right after I switched to winter tyres in November I guess, and I had told the employee at the tyre shop to set the pressures to 34/32 f/r. So it means I didn't check them in last five months. While switching to summers yesterday I told them to set the pressures, to 32/30. After I got the warning, I checked them and they were more or less correct at 32/30 (not sure how precise my Michelin digital gauge is). So the difference triggered the warning looks like 2 psi. But it is strange why the warning was for front left only and not for others and also not sure if it's possible for a tyre to keep its pressure for five months.

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I'm very surprised that it showed an error with those differences in pressure!

 

[tracktoy]

Yes the MK3 does tell you which tyre has dropped pressure. I get this a lot after a track day when i have to adjust the tyre pressure (which increases due to heat) but then next day tyres have cooled down and I get the warning.

From memory it just stores a pressure for each wheel and then using the sensor can see that wheel is being affected and has either increased or dropped outside of the range.

I had a Renault Lagoona many years ago and that would give you a warning on a cold morning (over sensitive sensors)

 

[andylong]

I believe the circumference of the tyre and so the signal frequency to the abs system is what determines the"pressure" stored. Change the circumference and the "pressure" is then different.
Mine, a mk2 just says check pressures but I think it works in the same way.
So changing tyres can trigger it even if the pressures are correct

 

[cupra14]

It's not (usually) a very sensitive system BUT it has the advantage that the wheels don't contain battery-operated sensors - which fail and I understand are costly to change.