Report in Autoexpress today : http://www.autoexpress.co.uk/car-news/consumer-news/97669/carmakers-accused-of-fitting-dangerous-tyre-pressure-monitors

Have you noticed any problems with yours? What is the approved method and standard?

Edited 9 November, 20169 yr by vrskeith

Both types are rubbish,

 

TPMS systems are a pain in the ass either direct or indirect,

 

Neither type work very well and unless its a slow puncture then tyres usually flat before light comes on

I don't know if this is still the case, but there used to be some cars where the recommended pressure was under 1.5bar, and hence the EU standard would require the TPM to alarm for a correctly inflated tyre!

 

Carmakers are facing claims that tyre pressure monitors fitted to some models are only capable of passing the lab-based vehicle type approval tests. These systems fail under real world driving conditions

 

Here we go again.

 

TBH I found the TPMS in my Octavia to be pretty reliable at picking up slow punctures.

When I had the Octavia I fitted the switch for TPMS as I wanted to fill a blank button space up!

 

But actually it did work on a couple of occasions. Once driving on the motorway and it bonged. Checked the tyre and it had dropped by quite a few PSI so topped it up.

 

Then another time and I checked the tyres to find a nail in the back one but pressure had only dropped a few PSI.

 

I think for a system that requires no additional hardware (apart from a switch and a wire) it is pretty good and should be standard on all cars.

 

Phil

Edited 10 November, 20169 yr by Phil-E

Looks like they rigged their testing unfairly against the ABS-based indirect systems, in a deliberate attempt to discredit them.

How realistic is it to make all four tyres equally underinflated?  Not impossible, but surely rare. 

 

 

Quote from their test procedure (link):

 

"However, the iTPMS on both VW Golf and Fiat 500L failed to issue a timely under-inflation warning in

at least 5 of the six tests performed by Idiada in which the test conditions slightly deviated from the

official test. Each of these tests aimed to represent driving conditions that can reasonably be encountered

on the road and included the following situations:

- A trip involving suburb roads and motorways at different speeds from 45km/h to above 90km/h with

all tyres under-inflated by over 20% (test D-01)

- A typical situation of driving 20 mins in a city at low speeds and then going to a motorway (around

100km/h) with all tyres under-inflated by over 20% (test D-02)

- Driving at high speeds above 100km/h with all tyres under-inflated by over 20% (on a German

motorway for example) (test D-03)

- Repeating the exact type approval test but on tyres with short and medium mileages of 400km and

800km accordingly with all tyres under-inflated by over 20% (tests D-04 and D-05)

- Driving with all four tyres calibrated at a critical level of 1.4bar (for example when renting a car and

not checking tyre pressure/how it was reset if no gauge is available) (test D-06)"

Looks like they rigged their testing unfairly against the ABS-based indirect systems, in a deliberate attempt to discredit them.

How realistic is it to make all four tyres equally underinflated?  Not impossible, but surely rare. 

This is why a number of these type of system use a 5th sensor - on the gearbox output. That way you can check all 4 wheels against the expected values.

 

From what I see on the road, TPMS is something that is necessary. I was at Ikea the other day and parked up next to a car with one front tyre completely flat and the other sagging badly. I went for a piece of paper to leave them a note and by the time I came back they had driven off.

This is why a number of these type of system use a 5th sensor - on the gearbox output. That way you can check all 4 wheels against the expected values.

 

From what I see on the road, TPMS is something that is necessary. I was at Ikea the other day and parked up next to a car with one front tyre completely flat and the other sagging badly. I went for a piece of paper to leave them a note and by the time I came back they had driven off.

There used to be an off car system that would detect and correct this sort of under-inflation. I believe it was called a "traffic policeman". 

When I had the Octavia I fitted the switch for TPMS as I wanted to fill a blank button space up!

 

But actually it did work on a couple of occasions. Once driving on the motorway and it bonged. Checked the tyre and it had dropped by quite a few PSI so topped it up.

 

Then another time and I checked the tyres to find a nail in the back one but pressure had only dropped a few PSI.

 

I think for a system that requires no additional hardware (apart from a switch and a wire) it is pretty good and should be standard on all cars.

 

Phil

 

Phil,

 

How easy was this to do and what was the cost etc?

Looks like they rigged their testing unfairly against the ABS-based indirect systems, in a deliberate attempt to discredit them.

How realistic is it to make all four tyres equally underinflated?  Not impossible, but surely rare. 

 

 

Sounds like they complaining about a situation the system isn't built to cope with.

 

AFAIR TMPS was there to inform the driver of an unexpected deflation of one tyre.

Not to inform the driver that they need to check their tire pressures in general.

The driver is ultimately responsible for the ongoing condition of the car, it would be a terrible mistake to take that responsibility away.

People already think they don't need to check their oil because that's what the light is for, and they don't need to look where they are parking because that's what the sensors are for.

 

If you take the responsibility away from people they act irresponsibly. I'm sure you're as shocked as me by that idea

In my experience Skoda TPMS works well alongside a weekly tyre check. Before I sold my 8 year old MkII, it started to lose pressure due to one of the alloys seal corroding. Recently my Mk III alerted me to a loss of pressure in the front left tyre. I replaced .2 bar but despite running my hand over the tyre and carrying out a reasonable visual check, I couldn't spot any fault. I was then more concerned that the alloy rim was corroding prematurely. It activated again 4 days later with the loss of another .2 bar and this gave me the incentive to give it a really thorough hand + visual check, which revealed a thin nail deeply embedded in the middle of the central tread with the head snapped off. Moral of the story for me is to believe the system when it activates.

Obviously someone still has an axe to grind with VAG..........

 

Bunch of fecking bankers........

 

Design a test & in reality it performs differently.....well then redesign the test to reflect what you consider to be reality...........

 

History is littered with human failure because "our design, figures, test, sample didn't perform in reality how we imagined.......

 

TBH. any TPMS system is only a GUIDE as it can't tell you that you have bald tyres/below the legal limit........

 

maybe that will now become another requirement because of thick people driving with bald tyres & wanting to sue because the TPMS didn't tell them...........

The TPMS are pretty good on my Mini JCW. Although one of them did lose communication with the car when on the dyno whilst the wheels were spinning at 150mph+ requiring the car to be taken off the rollers for the system to be reset which was quite annoying lol.

Tpms has always been fine for me finding slow punctures.

It doesn't, and isn't described, as being able to detect sudden pressure loss. If you have sudden loss, even on a direct system you should know about it before the light goes off.

The usual issue is not resetting the system after checking pressures. In gradual natural loss of pressure the system re-stores these new values over time as the 'reference' value. So you then need to drop your 3psi below this before the system would trigger.

It's why so many times SWMBO would drive around in the Octavia well below what they should be at - because the light never came on to tell her they needed pumping up. Even looking at them you could tell FFS.