TPMS

[galewis]

I noticed tgat Vagparts.com are selling the tyre pressure monitoring switch

https://sslrelay.com/s74326199.oneandoneshop.co.uk/sess/utn;jsessionid=15458dbe2c873e3/shopdata/index.shopscript

I forgot to order this option on my A3 and was wondering what else would need to be done to get tyre monitoring working?

 

[Beddie]

Some coding with vagcom and the sensors that fit on the inside of the wheel rims X4 iirc...

 

[d3fy]

It works off the ABS, so with a bit of luck it might already be in place and just the switch and VAGCOM needed

 

[steve184]

no sensors on wheels with this system. it works by calculating the circumference of the tyre via the abs sensor - as pressure drops the circumference changes ever so slightly and it alarms when it does

 

[Vertigo1]

You mean it detects the circumference has reduced by comparing the revolution speed of the wheel compared to the other wheels? Clever!

Only problem with this is if all your tyres are under or over pressure by the same amount the system won't be able to tell althought this is a tad unlikely I'll grant you.

 

[Dandle]

You mean it detects the circumference has reduced by comparing the revolution speed of the wheel compared to the other wheels? Clever!

Only problem with this is if all your tyres are under or over pressure by the same amount the system won't be able to tell althought this is a tad unlikely I'll grant you.

It only works by remembering the wheel speed that you set it at(for all four wheels), if pressure drops then the wheel speeds up and you get an error.

 

[cjp2k]

Same as the golf then, I specced it as I am useless at remembering to check my tyres.. and for £45 it seemed worth it

 

[marriedblonde]

Same as the MB B-Class as well although you get it for free in that

 

[jdp1962]

No way am I going to trust that. I think I'll stick to checking them myself once a week.

 

[RobinA3]

i am guessing this is not to be used as something that replaces the need to check your tyres weekly, i think its there so that if you have a nail or something in the tyre then you won't need to wait until you next do the check to find out its there.

 

[Beddie]

TPMS system retrofit guide albeit for a US car so may be some differences for UK models...?

http://oooo-a3.blogspot.com/2006/04/tire-pressure-monitoring-system-tpms.html

 

[Vertigo1]

It only works by remembering the wheel speed that you set it at(for all four wheels), if pressure drops then the wheel speeds up and you get an error.

Yes but the wheel speeds up and slows down as the vehicle does so it needs some way of measuring a discrepancy in this speed after compensating for the vehicle's speed. The only ways I can see this being possible is if it measures the wheel speed relative to the other wheels or it if it has some way of knowing the vehicle's speed other than via the wheels.

 

[Dandle]

Yes but the wheel speeds up and slows down as the vehicle does so it needs some way of measuring a discrepancy in this speed after compensating for the vehicle's speed. The only ways I can see this being possible is if it measures the wheel speed relative to the other wheels or it if it has some way of knowing the vehicle's speed other than via the wheels.

Yeah thats all id does, you pump your tyres up then set the system. If one wheel changes speed relative to the others then it sets of the warning. It actually works rather well. And gave me a warning with in 1/2 a mile when I changed tyre pressures on our car. Its only really to let you know if your car a developed a puncture while on a journey i guess. It was only £45 so well worth it in my book(same amount as a night in the pub).