Tyre pressure monitoring systems
What is a TPMS?
A Tyre Pressure Monitoring System or TPMS, monitors the air pressure in your tyres. The system tells you if the pressure falls below your cars recommended level. On most systems when the pressures fail, the system will show a red warning icon on your dashboard (link to dashboard lights) to tell you that he pressure or temperature has move to a potentially dangerous level.
Direct vs Indirect
Direct TPMS uses pressure sensors on the tyre to physically measure the pressure
Indirect TPMS uses other vehicle sensors such as ABS (link to Jargon Buster) to compare wheel speeds
Do I have a TPMS?
Back in 2012, new EU legislation required all car manufacturers to fit the TPMS system as standard to all new vehicles – making sure that your tyres are at the correct pressure for optimised safety.
If your car is older than this, it is possible to fit a TPMS as an aftermarket product.
If you have RunOnFlat tyres, a TPMS is fitted as a mandatory requirement.
Recent studies have shown that British motorists spent almost £1 billion a year on fuel just from driving on under-inflated tyres. So, always be sure your tyres are at the correct pressure to get the best possible fuel economy
Why is tyre pressure important?
To keep you safer, to increase the ife of your tyre, to improve your fuel economy.
Safety – the behavior of the tyre is connected to its inflation pressure. Key activities like braking and stability mean that you are required to adjusted the inflation pressures and keep as specified by the vehicle.
Underinflation can lead to thermal or mechanical overload as it overheats, in some cases it can lead to sudden destruction of the tyre itself. As the tyre is the only thing connecting you and your passengers to the road, it is very important that you check your tyre pressures regularly.
Tyre Life & Fuel Economy
Tyres naturally leak air overtime, especially in warmer weather. Fuel efficiency and tyre wear are affected by under inflation
It is always best to check your tyre pressures when your tyres are cold, usually if you have driven less than two miles.
You can use a tyre pressure gauge or most petrol stations have a facility for you to check and top up your pressures.
It is also useful to clean valves and check for leakage, you should also look to replace missing valve caps. And whilst your checking don’t forget to include your spare, just in case.
You’ll find an easy to use table in your vehicle’s manufacturers handbook telling you the correct pressures for your vehicle. Often this is also displayed on the arch of the driver’s door of your vehicle.
You can also use our handy tool – just pop your reg in, check the tyre size is correct and voila!
Although it may seem tempting to over inflate your tyres, your braking ability could be at risk. Not only that, but it reduces your traction on the road, decreases the life of your tyre due to inconsistent tyre wear and in extreme cases this could cause a blowout.
There are two units of pressure that are used to measure tyre pressure: bar (metric) and pounds per inch (PSI) which is the imperial measurement.
Both are often quoted together in user handbooks or tyre pressure stickers but be aware that if this is not the case you will need to use an appropriate pressure gauge to avoid confusion.
As with anything there are both positives and negatives to filling tyres with nitrogen over air.
Nitrogen molecules are bigger than normal air molecules and so it is harder for them to leak out. A tyre filled with nitrogen will maintain air pressure longer and so long term your pressures will remain more stable. When your tyre pressures are stable and correct you’ll benefit from lots of things including fuel economy and longer tyre life.