Active discussions

Please or to access all these features

Talk
AIBU?

Share your dilemmas and get honest opinions from other Mumsnetters.

Original poster

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

92 replies

NorwichMom · 29/07/2026 06:12

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.

OP posts:
Thread gallery
8
MildlyMoist · 29/07/2026 09:26

NorwichMom · 29/07/2026 08:44

No. I’ve rung another garage to ask them if it is a mot fail as the government website seems open to interpretation regarding whether a tpms light is a fail or not.

im pretty sure they’d immediately notice the constant light on the dashboard so I can’t just hope they don’t see it.

and if it’s against the law to pass it why are so many posters on here getting passed with the same fault?

garages don’t put stuff down as an advisory just because you haven’t heard of the fault.

Edited
Show quote history

Aren’t you cancelling the light once you check the tyres are okay? You can reset it yourself by confirming the pressures are okay. It might pop on again within a couple of days but it’ll get through the MOT even if it should be a fail if you’ve reset it just beforehand. My Skoda also has an overexcitable sensor on one tyre which causes this intermittently and when we check, the pressure is always fine so we reset it and carry on.

Original poster
NorwichMom · 29/07/2026 09:15

It’s a Vauxhall Astra. I don’t seem to be able to set the light off.

there definitely isn’t actual low pressure. Before this fault if there was low pressure it would tell me which tyre and what the pressure was. It now doesn’t read the pressure for any of the tyres. I’ve checked my tyre pressures and they’re fine

OP posts:
rougheredges · 29/07/2026 09:07

DD had exactly that problem. 1litre Ford fiesta (dreadful car for random things going wrong).
£120 per tyre to fix a sensor when the tyres were checked regularly and were fine.
What she discovered was she could reset the alert that showed on the dash by using the settings menu and it only came back on once she’d driven about 0.25 miles. Car didn’t get driven for MOT so she reset it when she dropped it off, passed the MOT and it came back on as she drove away!
DH was a bit twitchy until I pointed out we’d both driven cars for 20 years with no tyre pressure sensor - you just have to check you tyres the old fashioned way!

MiddleAgedDread · 29/07/2026 09:03

What sort of car is it? You should be able to cancel
the warning light once you’ve checked the pressure. Mine doesn’t go off automatically you have to go through various screens and options to cancel it.

Ineffable23 · 29/07/2026 09:02

But if the car tyres had low pressure then it could be sensing the low pressure. Instead of it being known to be a system fault.

Original poster
NorwichMom · 29/07/2026 08:53

Ok so the other mot tester in the village says if it’s a system fault (which it is) rather than just low pressure it’s 100% a mot fail.

OP posts:
somekindof · 29/07/2026 08:50

My car passed the mot for at least a couple of years with faulty sensor warning, then cost about 100 to replace them all when I finally got around to it.
An engine light is a fail, other warnings not necessarily.

Original poster
NorwichMom · 29/07/2026 08:47

tanstaafl · 29/07/2026 08:23

OP, I’ve got to ask, are your tyres losing pressure every few days - indicating the tpms is working fine ?

we had to change the valve units ( the battery was dying but you can’t only change the battery ) in all 4 wheels on a 2020 Ford Puma over the last 6 months. Our local Ford dealer charged £64 all in per wheel, so £500 seems steep.

No not losing pressure.

OP posts:
Original poster
NorwichMom · 29/07/2026 08:46

MiddleAgedDread · 29/07/2026 08:14

Also have a Honda that does the same, even the guy in the garage said his constantly comes on! never failed MOT although I can cancel the warning light once I’ve checked the tyre pressure is ok. It’s usually back on within a day or two though!

Show quote history

I can’t get the light to switch off even after checking the pressure

OP posts:
Original poster
NorwichMom · 29/07/2026 08:44

Sherararara · 29/07/2026 08:08

So you’re going to go to the garage and say “Hi, I’ve got a known permanent fault, are you ok to break the law and pass my car?” As opposed to taking the chance and claiming it’s the first you’ve heard of it and get it put down as a warning.

Show quote history

No. I’ve rung another garage to ask them if it is a mot fail as the government website seems open to interpretation regarding whether a tpms light is a fail or not.

im pretty sure they’d immediately notice the constant light on the dashboard so I can’t just hope they don’t see it.

and if it’s against the law to pass it why are so many posters on here getting passed with the same fault?

garages don’t put stuff down as an advisory just because you haven’t heard of the fault.

OP posts:
tanstaafl · 29/07/2026 08:23

OP, I’ve got to ask, are your tyres losing pressure every few days - indicating the tpms is working fine ?

we had to change the valve units ( the battery was dying but you can’t only change the battery ) in all 4 wheels on a 2020 Ford Puma over the last 6 months. Our local Ford dealer charged £64 all in per wheel, so £500 seems steep.

MiddleAgedDread · 29/07/2026 08:14

Negroany · 29/07/2026 06:45

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.

Also have a Honda that does the same, even the guy in the garage said his constantly comes on! never failed MOT although I can cancel the warning light once I’ve checked the tyre pressure is ok. It’s usually back on within a day or two though!

Sherararara · 29/07/2026 08:08

NorwichMom · 29/07/2026 07:31

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

Show quote history

So you’re going to go to the garage and say “Hi, I’ve got a known permanent fault, are you ok to break the law and pass my car?” As opposed to taking the chance and claiming it’s the first you’ve heard of it and get it put down as a warning.

BeethovenNinth · 29/07/2026 08:08

I had similar with my v old car recently but in my case it was an intermittent fault for another issue and luckily that day the light didn’t come on. I have spent 300 trying to fix it and it can’t be fixed and the car is ok

could you find a garage and ask if they will pass it as it sounds variable? I have never had a car with this level of sophistication - I have to check my tyre pressures manually - and assume that is what you do now anyway!

user1471543094 · 29/07/2026 08:02

I have this exact issue on my car (fiesta). I am able to turn it off through the vehicle settings. It does come back on after a certain amount of time but it's no big deal.
I'm in NI so different MOT process. My mechanic said that it wouldn't be a fail, but I be sure to turn it off before going to MOT centre.
I was quoted £90 per sensory plus labour.

Original poster
NorwichMom · 29/07/2026 07:38

Negroany · 29/07/2026 07:33

What £50?

Don't you get a free retest if you fail?

I've never had a failed MOT, so I'm not sure?

Show quote history

Only at same garage I think

OP posts:
Negroany · 29/07/2026 07:33

NorwichMom · 29/07/2026 07:31

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

Show quote history

What £50?

Don't you get a free retest if you fail?

I've never had a failed MOT, so I'm not sure?

Original poster
NorwichMom · 29/07/2026 07:31

Sherararara · 29/07/2026 07:23

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

Edited
Show quote history

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

OP posts:
Sherararara · 29/07/2026 07:23

Negroany · 29/07/2026 07:05

Take it to a different garage then.

Show quote history

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

Londonrach1 · 29/07/2026 07:10

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

Keepthecat · 29/07/2026 07:07

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.

Original poster
NorwichMom · 29/07/2026 07:07

usererror99 · 29/07/2026 07:06

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.

OP posts:
usererror99 · 29/07/2026 07:06

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)

INeedAnotherAlibi · 29/07/2026 07:05

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.

Negroany · 29/07/2026 07:05

NorwichMom · 29/07/2026 07:04

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.

Show quote history

Take it to a different garage then.