Did you know that if you own a vehicle that's 2014 or newer, it's almost certainly fitted with some form of TYRE PRESSURE MONITORING SYSTEM (TPMS)


Many vehicles are equipped with TPMS systems that have sensors mounted on the inside of the wheels, attached to specialist tyre valves. These components degrade over time and need to be regularly checked by a tyre expert and serviced or replaced as required.

What is TPMS?

The main purpose of the Tyre Pressure Monitoring System (TPMS) in your vehicle is to warn you that at least one or more tyres are significantly under-inflated, possibly creating unsafe driving conditions.

The TPMS low tyre pressure indicator is a symbol that illuminates on the instrument panel in the shape of a tyre cross-section. This symbol is also used to indicate when the system is not working correctly.

Your local tyre experts are able to perform various tests in order to check both your tyre pressures are correct and your TPMS is functioning correctly.

Did you know that TPMS is also tested as part of the MOT?

Vehicles first registered after January 1st 2012 must have the TPMS checked during the annual MOT.

If the system shows a system malfunction then the vehicle will fail the MOT.

A system malfunction is displayed by the TPMS warning lamp flashing for 60-90 seconds when the ignition is turned on. The lamp will then remain on and solid during driving.

Why is TPMS serviced?

Air valves are fitted to all car wheels to allow the tyres to be easily inflated / deflated. The valve is therefore acting as a seal too, keeping the air inside the tyre whilst you're driving.

Before TPMS, most vehicles were equipped with a relatively standard rubber valve. Rubber naturally degrades over time and this degradation can be exacerbated in extreme weather conditions or when exposed to harsh chemicals. So, these rubber valves would be replaced with every tyre job and would be built into the final cost of the job. As an example, you may have seen "Includes valve, balance & disposal" on your past invoices.

TPMS valves are a little more specialist as they have been adapted to allow the internal sensors to be attached to their base on the inside of the wheel. This means that the valves are of a much higher specification, to withstand the additional weight of the sensor and the G-force applied to them during rotation.

Unfortunately, there are many different manufacturers of this equipment and over the years the technology has developed resulting in many different sensors to exist, each requiring their own specific type of valve. These valves can be rubber but it is also common to see metal valves fitted to vehicles too. Whether rubber or metal, it is important that the valve system is replaced or at the very minimum serviced to maintain the seal between the wheel and the valve, keeping you safe on the road.

How is TPMS serviced?

The first job of the tyre expert is to identify the type of valve fitted to your wheel. This will then determine the type of service, full rubber valve, full metal valve kit, or a metal valve sealing kit. Some metal valves can not be replaced in their entirity and can only have the sealing kit replaced. 

If the parts are available, then the service can be completed there and then as part of you tyre replacement or repair. Sometimes, with the less common parts, they may need to be ordered in especially for you.

The cost of the service will likely depend on the type of service being performed. Generally speaking, the full kits tend to be more expensive than the sealing kits, with some metal valve kits being considerably more expensive. Your tyre expert will explain the costs specific to your vehicle.

What if the sensors are not working?

Tyre pressure sensors are battery powered units that are transmitting the air pressure from each of the tyres to a control unit / reciever via a low frequency radio signal.

All sensors will eventually fail once the battery is depleted, which on average is somewhere between 5 and 8 years after first fitment. If your car is over 5 years old and the original sensors have not been replaced, be prepared for the eventuality that the sensors will need to be replaced.

Other issues can result in a sensor needing to be replaced too;

  • Damaged valve on a sensor where the valve is not replaceable
  • Valve locking nut, cap or core corrosion where the valve is not replaceable
  • Sensor damage from exposure to incompatible chemicals such as non-TPMS tyre sealants
  • Water damage from an accumulation of water in the tyre 

The original equipment (OE) sensors can vary in price massively and in some cases can be in excess of £150 each, fully fitted and coded to your car. Our garage partners are able to supply high specification aftermarket sensors to replace over 98% of faulty sensors that they come across, at a much more reasonable cost.