TPMS — Your Tyre Pressure Warning Light Explained

The TPMS warning light — a horseshoe symbol with an exclamation mark — illuminates when one or more of your tyres drops significantly below its recommended pressure. Since 2014, all new cars sold in the EU and UK have been required to include a TPMS as standard. When the light comes on, you should check all four tyre pressures as soon as it is safe to do so and inflate any under-pressure tyres to the correct level. In most cases, the light will go out once pressures are corrected and you have driven a short distance.

If the light comes on while you are driving, reduce your speed moderately and check for any obvious signs of deflation — pulling to one side, unusual vibration, or a change in handling feel. If a tyre appears visibly flat, pull over safely and do not continue driving on it. A flat tyre driven at speed can cause a blowout and loss of vehicle control.

Some TPMS systems use a flashing warning light to indicate a system fault rather than a pressure issue — for example a sensor with a flat battery. If the light flashes for 60 to 90 seconds before staying on continuously, this typically indicates a sensor issue rather than an actual pressure problem. Have the system checked at your next service, or contact Castle Mobile Tyres if you suspect a tyre issue alongside the warning.