What is TPMS?

How tyre pressure monitoring systems work

You may have heard of TPMS or seen the light on your car, but are you actually aware of what it is and how it works? TPMS stands for Tyre Pressure Monitoring System. It’s an electronic system that monitors the air pressure in tyres, and is found inside them. Tyres that are over or under inflated activates the TPMS warning light on your dashboard. This occurs when one or more of your tyres is around 10% below the recommended inflation pressure.

There are two types of tyre pressure monitoring system; direct and indirect. The illumination of the warning light on your dashboard is the final step in the process of either of these.

Indirect TPMS

Indirect TPMS relies on the tyre speed sensors that the anti-lock brake system also uses. This system measures the rate of revolutions each wheel makes, and this is used by computer systems on your vehicle to compare with other data like speed.

When the revolution of each wheel is conducted, the computer can then interpret the relative size of the tyres on the vehicle. If a wheel begins to spin faster than is expected, the computer understands this as the tyre being underinflated, and the warning light in the dashboard is then alerted.

An indirect TPMS isn’t measuring the actual pressure of your tyres. It is simply measuring the speed your tyres are rotating at and then sends signals to the computer that will activate the warning light if something seems to be incorrect.

Direct TPMS

A direct type pressure monitoring system uses sensors located in each tyre that are able to monitor the actual pressure levels.

The sensors used in TPMS can also provide tyre temperature readings. This monitoring system is able to send all the collected data to a central control module. It is here that it is examined and understood. If the tyre pressure result is lower than it should be, the warning light on the dashboard will light up. Most direct TPMS will send all of this data wirelessly. Every tyres’ sensor has a unique number, which is helpful for when they need to be distinguished from other pressure readings taken from other vehicles systems, as well as other tyres on your own car.

If you want to replace your current system with a direct TPMS, you’ll need an experienced and expert technician to do this.

Both tyre pressure monitoring systems serve the same purpose and work to activate the same warning light if needed. TPMS systems can deliver very accurate readings and alerts if need be, though it should not be considered as a replacement for manual air pressure checks. You should continue to check the air pressure in your tyres regularly.

Here at Eden Tyres we are experts in tyre pressure monitoring systems. We also have TPMS sensors in stock at every one of our branches, of which are suitable for 98% of our vehicles.

If you need more information on your TPMS system or would like advice on getting a new system fitted, you can get in touch with a member of the team by visiting our contact page, giving us a call on 0345 299 7955 or by visiting us in store today.