Tyre Pressure Sensor - a bit rubbish?

[Ootohere]

All new cars in the UK from the 1st January 2015 had to have TPMS as standard.  Skoda were 'Simply Clever' and complied with that legislation.

[Beddau]

Yes  engine letters are  CHYA

[Beddau]

13 minutes ago, Roottootemblowinootsoot said:

All new cars in the UK from the 1st January 2015 had to have TPMS as standard.  Skoda were 'Simply Clever' and complied with that legislation.

Yes all Citigos post 2015  have TPMS  I am trying to find out why my system is working when removing a tyre off the wheel there is no TPMS  sensor fitted I purchased another wheel from E-Bay for a 2016 Citigo & the replacement wheel has no sensor only the valve yet tyre pressure monitoring is working, so is the TPMS gettingits information from the ABS sytem>.

[Ootohere]

Until very recently in some top end vehicles (Not Citigo's) there was the simplest system and the ABS system did the job.

No valve sensors or sensors in wheels.  

 

You would have got that answer with a single question in the Citigo section.

Edited 4 February, 2020 by Roottootemblowinootsoot

[Breezy_Pete]

20 minutes ago, Beddau said:

is the TPMS gettingits information from the ABS sytem

I answered this four hours ago, didn't I?

 

[jafo]

@Beddau

 

Do you have separate value of the pressure for each wheel or only indication when something is wrong and icon to check the tyre? 

 

If the latter - the information about the pressure is guessed from the speed of the wheel - ABS sensor - andif it's too different to the other wheels for too long - system reports it as problem with the tyre. 

 

Sometimes it's false-positive - you need to stop the car, turn the ignition off for few seconds - so car will think that you've fixed the problem and then you can press the button to reset. If you get warning again - something is wrong. 

[gumdrop]

Awful system, tells you tyre air pressure differs on at least one tyre. It does not tell you which one.

a tyre pressure gauge may show no difference. A so and so if you are towing a caravan on the M5

for instance. You need to pull off the M5 and check all four tyres (and the spare while you are about it)

then struggle to get back on the motorway.

 

[Beddau]

I have had a bit of an outing with TPMS. Only had the car for four weeks. After driving for a few miles, the tpms warning came up checked all tyre pressures N/S  front showed 20 psi so I pumped it up to 32 psi after a few days a 10 miles or tpms warning again checked n/s front down to 20 psi. ordered a spare wheel put on the spare & took the deflating one to my tyre specialist & he found a  micro small leak from the inner part of the alloy wheel probably caused by accident damage as the car had been in a punch up but fully repaired.  I order a good wheel from E-Bay & had the tyre fitted from the leaking wheel. all fixed now.  The next day while on the motorway tpms came on again pulled over & fitted the spare onto NSF.   When I got home Checked the pressure on the NSF that I taken off & the pressure was 32 psi. took off the spare & fitted the alloy back on.  Checked all tyre pressures all OK reset TPMS & no warning has shown for a week, fingers crossed. My TPMS warning is just the tyre image indicates when something is wrong but it tells lies. and wastes time faffing about for a loss of pressure that is not their. So the chances are that I am not suppose to have sensors on each wheel & thats why I can't find any. So the ABS system does the job. Thanks for the advice, but I am to old to be be messing about with tyres at my age, after 60 years of motoring & 40 different cars which I have never had a tyre problem before it seems crazy that I had to change a wheel on the hard shoulder of a motorway in the dark on a 3 year old car.

[chimaera]

40 minutes ago, Beddau said:

I have had a bit of an outing with TPMS. Only had the car for four weeks. After driving for a few miles, the tpms warning came up checked all tyre pressures N/S  front showed 20 psi so I pumped it up to 32 psi after a few days a 10 miles or tpms warning again checked n/s front down to 20 psi. ordered a spare wheel put on the spare & took the deflating one to my tyre specialist & he found a  micro small leak from the inner part of the alloy wheel probably caused by accident damage as the car had been in a punch up but fully repaired.  I order a good wheel from E-Bay & had the tyre fitted from the leaking wheel. all fixed now.  The next day while on the motorway tpms came on again pulled over & fitted the spare onto NSF.   When I got home Checked the pressure on the NSF that I taken off & the pressure was 32 psi. took off the spare & fitted the alloy back on.  Checked all tyre pressures all OK reset TPMS & no warning has shown for a week, fingers crossed. My TPMS warning is just the tyre image indicates when something is wrong but it tells lies. and wastes time faffing about for a loss of pressure that is not their. So the chances are that I am not suppose to have sensors on each wheel & thats why I can't find any. So the ABS system does the job. Thanks for the advice, but I am to old to be be messing about with tyres at my age, after 60 years of motoring & 40 different cars which I have never had a tyre problem before it seems crazy that I had to change a wheel on the hard shoulder of a motorway in the dark on a 3 year old car.

It's been pointed out a few times now on this thread that your car most definitely does not have pressure sensors in the wheels. Like many other models, it's using the ABS wheel speed sensors to monitor tyre pressure by proxy: if a tyre is deflating its rolling radius will change and the ABS will detect this as a change in the speed of the individual wheel. If this change exceeds a set threshold the system will warn you to check your wheels. If you have checked them and everything is ok, make sure to hold down the button on the dash until you hear a ding: this resets the system and tells it everything is ok again. If you are getting consistent false positives this could indicate a fault with the ABS and it is worth having this checked over.

 

In the meantime, I'd suggest you get yourself a tyre pressure gauge in Halfords or somewhere like that so that you can check pressures before going to the effort of changing the wheel.