AIBU to disable a faulty tyre pressure warning to pass the MOT?

[NorwichMom]

I’m aware the latter option probably isn’t legal. Keep in mind the car is old and I will keep it until it dies so won’t be passing this problem onto someone else.

I have a light on the dashboard because the tyre pressure monitoring system valves have failed. I took it to a garage a year ago who said it wouldn’t be a mot failure. That it would be about £500 to fix and they recommended I learnt to live with it.

Fair enough i thought. None of my previous cars have had a tyre pressure monitoring system I can live without it. So bought a pump which plugs into the cigarette lighter thing and I regularly check my tyre pressures and inflate if needed. Old fashioned maybe but safe.

Turns out it is a mot failure after all. The mechanic suggested I find someone who can do something to my car to make my car think it hasn’t got a tyre pressure monitoring system and then the light will go out. Someone has offered to do this (I think for free). Or I pay circa £500 to have it fixed.

AFAIK the light still has to come on on the dashboard when the car is started - if someone disables it completely it will still be an MOT fail.

Are you sure it’s not a sensor issue? Mine was replaced two years ago for about £20.

Interesting, thank you. Did not know that. If that’s right I’ll have to get it fixed.

I’m not sure what the sensor is. I’ve had valves fail before individually and had them replaced for about £20. So months ago I took it to Mr Tyres and they couldn’t fix it and didn’t know what the problem is. So my mot mechanic (who won’t do the job as he doesn’t have the right equipment) said he thinks it’s not the module which has failed but a battery in the valve. A garage which can fix it agree with his assessment and say the batteries often die at around ten years old and when one dies it knocks the whole system out.

It’s something like £125 per valve which needs doing. It might be one, but they’d recommend getting all 4 done as the batteries are all the same age . 🤷‍♀️. There would be some sort of discount i believe for getting all 4 done at the same time as they only have to reprogram it once.

Oof that is quite expensive 😬

Have you tried taking it to an independent mechanic and have them plug an OBD reader into it? It’ll tell you the exact fault at least.

The actual sensors are around £7.50 per wheel - my car doesn’t tell you which one (2013) so have to replace all of them whereas DS car (2015) does so only need to replace the faulty one
We bought out own fault code reader so can reset the settings much cheaper than paying a garage

How old is old? If the car is older than 2012, working TPMS it isn’t required for the MoT. Mine had a fault last year and it passed with no problems.

I bought a fault code reader myself and tried the whole reset thing. That was like a year ago so I can’t remember the details other than it didn’t work. I have some vague memory of holding some device near one wheel and you have to work your way round the different wheels and the horn honks when there’s a fault or something weird. My mot guy is an independent place and he has a fault code reader and I think one of these reset gadgets as well because he told me he’d tried to reset it but couldn’t.

My ten year old Honda Civic constantly has the tyre pressure light on. I've had everything done to fix it, including have Honda replace the sensor (that was about £20, not £500). Nothing works. It can be turned off but that only lasts about half an hour.

It's never failed its MOT because of it.

its 2016. Yes, the mechanic said this yesterday which is irritating. Surely it’s either ok for it not to work, or it’s not ok for it not to work. No idea why it’s safe for a 2011 car but not for a 2013 car! It’s bonkers rules like this which annoys me so much.

This is my massive worry. Someone told me that sometimes they can’t be sorted. In which case i will have to scrap a car which drives fine and has 60k on the clock. If your car is ten years old it should be a mot fail. So you are very lucky your garage passed you. The garage passed it for me last year with the light on but the same garage has refused to pass it this year. I guess I could maybe try other garages and see if someone is prepared to pass it.

Have you tried reading forums for your car to see if there are any suggestions?

I did for mine, which is where I found that it's a "known fault". Not that Honda themselves accept that, even though they also can't fix it!

I had exactly the same thing a year ago on my 2016 car.

The battery on the sensors last about 10 years then need replacing.

I have done all the research and the answer is no- you need to replace them.

£500 is a little steep and the price for all 4. I just got the garage to replace the one that was faulty. The others subsequently died a few months later so I have had all 4 done now. Total was about £450.

Not "garage passed you", this has been going on for years. It's been passed every year, and it's never the same garage (I just go wherever has a slot at the time).

It's never crossed my mind that it might fail due to it. And I've never mentioned it to them.

Last service (I'm not bothered about getting my cars serviced, it's been done twice in the ten years I've had it) they phoned me to ask what the light was for, so I told them and they said OK and just left it.

@Negroany also if you need to fix it/want to then you probably need to take the next step which I’m doing as it sounds like you have tried the valve stem replacement at £20 which is what I’ve tried (and has worked in the past).

the next stage is having the electronic sensor unit which is attached to the valve replaced. This is what the bigger cost per wheel is.

Same for DH’s Honda Jazz - Hondas are notorious for it. His is 2018 reg and it’s not been an issue.

I guarantee that won't resolve it on my car.

It can't be that, as it's been on since 2017. The car is a 2016 plate.

But, it's never been an MOT issue.

From the gov website; https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/5-axles-wheels-tyres-and-suspension

The TPMS warning lamp (see diagram 3) will generally illuminate and go off again when the ignition is switched on. If the system has identified a previous pressure loss, the lamp will remain illuminated. This does not automatically mean the system has a malfunction. In the event of a system malfunction, the lamp may flash a number of times and then remain on.
Warning messages on dashboard displays are not a defect in their own right, but may assist the tester in determining that the warning lamp is illuminated because a malfunction exists.
If it is unclear the warning lamp is indicating a system malfunction and not a simply indicating that one or more tyre pressures are low, then advisory information should be added to the test result.

it’s only not a fail if the light is lit simply due to low pressure. If the garage isn’t sure if it’s a system malfunction or low pressure then they can pass the car but issue an advisory (which is what I had last year). But this year he has said that he knows it’s a malfunction therefore he has to fail it. Now I admit that last bit isn’t explicit on the govt website but I can certainly see the interpretation that you can only do an advisory if it’s unclear if there is a malfunction. But the website doesn’t actually say what to do if it’s clear it’s a malfunction…….but the garage say it’s the next step up?

I mean if I can take it to a different garage and get it passed that would be ideal.

And his has passed the mot? I am beginning to think I need a different garage.

Take it to a different garage then.

Mine kept going off. I’d check the pressure, reset it, it would stay off for a bit then back on again. Eventually one of the springs snapped. Had that replaced and the light stopped coming on so I’m convinced it was getting triggered because the spring was dodgy. I’d get another opinion to see if it’s anything else around the wheels.

I have a Ford - I had that light last year and was told any warning lights were an MOT failure. Duly replaced 2 sensors. 4 months later the light is back on. I’m holding out for another few months until the next MOT to get them done again (assume different ones this time)

This is what i don’t understand. Why some garages say it’s an mot fail and others don’t.

Just about doing the OBD - check the manual or Google it - you may be able to find fault codes yourself from the car's own system. Even my 2010 mini had that.

My 19 year old skoda had the same fault and passed mot every time as it was a known issue for about 5 years as every sensor had been changed. It helped the garage that changed the sensors also mot it. Sadly at 20 years of perfect service we let this amazing skoda go before the 20 year mot

This. Claim ignorance if it gets mentioned. Not rocket science.

Sure. But I also don’t want to keep wasting £50 if other garages are also going to fail it. I think I’ll have to ask them first if they’ll pass it