posted 3 years ago

New Rules: MOT Fail For Faulty Tyre Pressure Monitor

New Legislation Makes It Harder To Pass MOT

Motorists could face higher repair bills as new legislation ensures a vehicle with a tyre pressure monitor cannot pass its MOT if the system fails, TyreSafe has confirmed. The not-for-profit safety organisation added that new cars must have a pressure monitor by law, so the new regulation could impact upon millions of motorists.

How A Tyre Pressure Monitor Works

A monitor incorporates a sensor within each wheel. If the pressure is to high, or to low, the motorist is informed via a message on the dashboard. A basic system has a warning light that confirms there is a problem with one or more tyres, whereas a sophisticated system confirms which corner(s) to inspect. The motorist can then confirm the diagnosis using a manual gauge and adjust accordingly.

Important Safety Feature

A system of this nature is an important safety feature as tyre pressure influences how a car brakes and corners. Incorrect pressure also prematurely wears a tyre, increases fuel consumption, and ensures a vehicle produces more pollutants. On this basis, it seems fair that any malfunction is an MOT issue (despite the cost).

Maintenance Required

A monitor should work reliably for years but every system requires maintenance and repair. Typical problems include a flat sensor battery or failure due to corrosion. Parts can also be damaged when changing a tyre. On this basis, some motor manufactures recommend replacing the valve cap and other core components at this point.

Monitor Cannot Be Removed

A motorist might be tempted to remove the monitor to bypass MOT issues. This is a false economy. If the vehicle had a monitor when it left the factory, it must be present and working to pass. 

TyreSafe Discusses Monitoring Systems

TyreSafe Chairman, Stuart Jackson, explained that monitoring systems have been gradually introduced “into the market over a period of years and with little or no fanfare to help educate motorists”. He added that repair stations are “telling us that they’re encountering a lot of customers who either aren’t aware of how these systems work (and need to be maintained) or just see them as an expensive luxury rather than the crucial safety feature”.

Video Explains Tyre Pressure Monitors

TyreSafe – that strives to make the roads safer by informing motorists about a range of tyre-related issues - has produced a brief video to “help motorists understand the safety features of this technology.”


Another useless EU law designed to push up the cost of motoring, unfortunately there are more motoring shocks to come from the EU, and our treacherous politicians will back them all the way.

So now they are bringing out this law, I have a rav4 t180, an that I had to replace a valve to pass my mot last year at price of £130. If it was the unit itself, it will be £200,this is a good idea to have on a car but pricy...

This is mad reason why I'm saying this is because on my side wall off tyres it says pps is 51 and I and every1 else knows that's far 2much so I keep mine at 34. Can any1 tell me if that is wrong what I've been doing for years

I suspect their purpose is not to protect the car owner but to protect others from accidents. I strongly suspect that the vast majority of motorists only check tyre pressure when they notice a partially flat tyre or start to feel some problem - even then there are maniacs who will carry on driving not knowing what to do.

Not all TPMS systems are as you have detailed in the article. Many of the sensors you refer to do not have a battery. They are solid state sensors. There are also systems which do not rely on individual sensors but on the rotation of each wheel. This kind of TPMS is more common but it also has its drawbacks. It tends to work on rapid pressure drops. So if you have slow pucture it may not always sense this. It usually takes a few miles of driving before a TPMS actually becomes active when the tyres have warmed up. There also one other major safety factor regarding Run Flat tyres which many people who drive run flats are not aware of. If you get a pucture the tyre is OK to drive on if the 50/90 rule is adhered to. This 50mph max for no more than 90km before you must replace the tyre. I have witnessesed many tyres that have litter ally been hanging onto the inner bead by threads as excessive speeds destroys the tyre from the inside very quickly depending how fast it is driven on once punctured. Regardless if you have TPMS and / or Run Flat Tyres you still need to check tyre pressures once a month.

I wouldn't rely on pressure sensors anyway. I'll continue using my reliable tyre pressure gauge whatever happens.

Who on earth thought that one up. Waste of time bits of kit. No one asked us, the consumers.

I've got a 5 year old bmw 3 series,in that time I've had 3 out of 4 sensors replaced ,just waiting for the last one to go.these systems are just not worth having,it's better and easier to check the pressures weekly

I have a 15 year old BMW. Some of the tyre sensors have at some point been damaged or removed by previous owners over the years thus sending out constant alarms. I have decided to hide the alarm symbol on the dashboard by covering it with tape however, like everybody else who is lucky enough not to have this nuisance system fitted, I check my tyre pressures weekly as standard and find absolutely no need for this annoying warning system at all.

Just another gimmick to appease the car makers and raise the cost for the motorist....ensures more early scrap cars (due to repair costs) and as a car takes more energy to make than it consumes in it's lifetime, it's bad for the about double standards by governments. They want car use to decrease yet want the tax from new cars, car tax - you and I say road fund tax - fuel duty, VAT, etc. - double standards again.

Just further reinforces the wisdom behind buying an older car with fewer systems to fail. I now have a 2000 V70 diesel and and equally old Defender. Both mechanically straightforward, both reliable and plenty of spares new and s/hand. Whatever happened to checking the condition and pressures of your tyres once a week? The more things that are taken out of a driver's hand will lead to less attention being paid to the actual driving of a car.

There is no way of tesing TPMS systems. MOT testers will simply look out for any failure indicators on the dashboard. Originally this element of the MOT was not going to apply retrospectively to cars that happened to have been fitted with TPMS as an 'extra' prior to 2012 (when TPMS became mandatory), but now it will apply to any car with it fitted whether it was a requirement at the time or not. There are millions of cars on the road that do not have this system (which does nothing except 'warn') but there is no requirement to have it fitted retrospectively so its odd that the test should be applied in this way. My 13 year old Laguna passed with 2 failed sensors this year but I was told they will have to be replaced at a cost of £70 each to comply next year.

Most cars work of the wheel speed sensor, and work on the rotataion of the wheel how is this checked??

My car has "secondary" TPMS (2014 Audi S8) does not have individual TP monitors but uses suspension rebound rates and wheel speed sensors (ABS ones) to detect variations. How will MOT Test centres test that?