[sunscreemer]

Hi guys,

Just been driving home from work and my tyre pressure sensor has gone off (got a set of 18" Chicago's). Got home and checked all tyres and they seem fine. I've reset the unit and was going to see if it goes off again. Anyone any history of this? Is the unit oversensitive?

Thanks,

Mark

 

[cb391]

Mine went off last winter when it ws -3F. Tires measured 30PSI instead of the recommended 34PSI. Pumped them back up to 34 and light turned off. If I remember the 18" tires require 37PSI. Generally the wheel sensors are pretty reliable. When you check the tire pressures it is also a good time to check the pressure in you emergency spare if you have one. I found mine needed air when my other tires needed air.

 

[sunscreemer]

Just been to check with my portable inflator (albeit a rubbish one!), osr tyre under pressure and i can now see a screw sticking out. Only got car a month ago and two months previous had to buy brand new tyre in my old car due to a nail stuck in it. 12 months previous had to replace same tyre in my previous car to that for same reason!!!!

 

[Mercilessswine]

Tyre pressure monitering is done using the abs sensors to calculate the rolling radius of the tyres and therefore if it detects one wheel starting to spin faster (radius decreasing due to low pressure) it brings the tyre warning light on. When ever you adjust pressures or change wheel size you need to relearn radius values by resetting the button. Also something else to consider if changing wheel size it needs to be coded at your dealer to enable esp to function correctly.

 

[evolvingpowercat]

One time my tire pressure has gone off it has been the space saver spare in the trunk that needed a few PSI added to it. Check that one too. The low pressure tire warning has saved me big trouble twice now when I picked up metal bits in a tire and got a tread leak and let me get problem fixed before tire ran flat and got ruined.

I don't agree with the prior post that says tire inflation is derived from ABS sensor measuring wheel spin rate.

I understand that there is a small module inside each wheel right behind the tire stem that has a pressure sensor and wireless transmitter that signals the measured pressure to a control module in the car. The service manual has documented this and talks about how it transmits more often when the tire is in rotation and less often when the car is stopped to make the battery last longer. The service manual documents how to have your Eos "learn" a module if a module ever needs to be replaced.

There is a battery in each module that VW expects to last about 10 years. Time will tell.

 

[Mercilessswine]

yes for the american market seperate sensors are used in each wheel however the original post was form someone in the uk so i was answering using uk spec info sorry for the confusion

 

[davidp]

I've done 32k miles on my rear tyres (pirelli rossos) but they are still on 4-5mm. Tyre pressure warning light lit up on Sunday so stopped to check tyres. Visual only as had no gauge but all looked OK. I'd checked all tyres pressures a few days before so assumed it was just a fluke
I reset warning switch and carried on. Later that day suddenly felt a strange rumbling from the rear pulled over and rear offside tyre flat with a big nail in the tread. So emergency wheel change required (and yes it had started to rain, Grrr)
Bit late but lesson learnt, will always carry a tyre gauge and pump for next time light comes on

 

[neh321]

I've done 32k miles on my rear tyres (pirelli rossos) but they are still on 4-5mm. Tyre pressure warning light lit up on Sunday so stopped to check tyres. Visual only as had no gauge but all looked OK. I'd checked all tyres pressures a few days before so assumed it was just a fluke
I reset warning switch and carried on. Later that day suddenly felt a strange rumbling from the rear pulled over and rear offside tyre flat with a big nail in the tread. So emergency wheel change required (and yes it had started to rain, Grrr)
Bit late but lesson learnt, will always carry a tyre gauge and pump for next time light comes on

Same thing happened to me yesterday. Tyre pressure warning light came on; I know it's not usually joking so slowed down and changed into l.h. lane. Then came the loud rumbling and car started to shake a bit so I pulled in right away. N/S/R tyre completely flat. Soon change that, I thought. Except there was no bit if bent wire in the toolkit to take the wheelnut covers off, so I was stuck and had to call out the garage. They insist all cars come with the bit of bent wire but I have never had my spare wheel out and there simply wasn't one. Whole job took about an hour and a half then I was on my way again, but of course had to get a brand new tyre..

 

[davidp]

That's a coincidence but shows the trye pressure light means business. I'd have been lost without that bit of bent wire though, don't think reshaping a paper clip would do the job
Two new tyres been fitted today!