What Does It Mean When Your Tyre Pressure Warning Light Comes On?

What Does It Mean When Your Tyre Pressure Warning Light Comes On? Header Image

Have you ever seen a little tyre pressure warning light on your dashboard? It can be a bit alarming but don't worry; it's a common issue that can happen to anyone. In fact, it's one of the most common causes of breakdowns.

Essentially, your car's onboard computer is telling you that your tyre pressure is too low. But why does it matter? Well, having the correct tyre pressure is crucial for your safety on the road and preserving your tyres' lifespan.

When your tyre pressure is low, it can affect your vehicle's handling, fuel efficiency, and overall safety. That's why it's so important to understand tyre pressure levels and how to notice everything from a slow leak to a puncture. Follow along as we dive into why the warning light comes on, how to fix it, and some helpful tips to keep your tyres in tip-top shape.

Why Tyre Pressure Matters

As mentioned, ensuring that your tyres are at the right pressure is essential for your safety on the road. Your vehicle's handling, fuel consumption and overall tyre lifespan are all directly affected by the pressure of your tyres.

When your tyre pressure is too low, more of the tyre's surface area comes in contact with the road, which increases friction and makes it harder for your car to move. This can also increase fuel consumption, which can be costly in the long run.

On the other hand, when your tyres are overinflated, there is less contact with the road, which can lead to poor handling and less grip. This is particularly dangerous in wet conditions or when braking suddenly. Overinflated tyres are also more likely to suffer from blowouts or punctures, which can be costly and potentially fatal.

Checking your tyre pressure regularly is important to maintain optimal performance and safety on the road. It's recommended to check your tyre pressure at least once a month, ensuring it is at the manufacturer's recommended pressure. This information can typically be found in your car manual or on a placard inside the driver's door.

Tyre Pressure Warning Light: Why It's On

If you're driving and your tyre pressure warning light suddenly comes on, don't ignore it. As mentioned above, tyre pressure is an important factor regarding road safety. This warning light means there's an issue with your tyre's pressure, and you need to act as soon as possible.

There are various reasons this light might come on, and we've listed them for you.

Slow Leak

One of the primary reasons your tyre pressure warning light might come on is a slow leak in your tyre. A slow leak may not cause an immediate issue but can lead to severe problems if not addressed promptly. If you suspect a slow leak is the cause, we recommend taking your vehicle to a local garage as soon as possible.

Faulty Wire or Sensor

A faulty wire or Sensor is another common cause of the tyre pressure warning light coming on. The tyre pressure monitoring system utilises sensors to measure the pressure of each tyre. If one of these wires connected to the sensor is damaged, it can trigger the warning light.

In this case, you should let your mechanic examine the system and fix or replace the damaged wires or sensor. How do you know if you have a faulty wire/sensor or the light is due to a real issue? If the light flashes every time you start your car and then stays lit up, it usually means the TPMS isnt functioning as it should.

Temperature Changes

Temperature fluctuations can also cause the warning light to come on. When the temperature outside changes, the air inside the tyres also alters its pressure, which can set off the sensor.

An early morning drive on a cold day might trigger the light to come on. You'll know that this is likely the cause if the light goes back off. This means that whatever caused the change in pressure has since been fixed and isn't likely anything ongoing or serious.


If your car runs over a nail or sharp object, the tyre can puncture and give you a flat tyre or a slow leak. A puncture can cause the warning light to come on too. If you notice a puncture, have the tyre repaired (if the puncture is in the middle 2/3rd's of the tread) else replace the tyre as soon as possible to avoid dangerous situations on the road.

Incorrect Tyre Pressure

Last but not least, the simplest potential cause of the tyre pressure warning light is having incorrect tyre pressure. Sometimes, drivers don't check their tyre pressure, resulting in uneven pressure distribution. The good thing about this is that there's a simple fix: head to your nearest garage forecourt and fill your tyres with air.

How to Fix Low Tyre Pressure

The good news is that fixing low tyre pressure is relatively simple, and you can do it yourself. All you need is a tyre pressure gauge and an air compressor. Tyre pressure gauges are inexpensive, and you can buy them at any hardware or auto supply store. Air compressors are all still commonly available at petrol stations.

First, you need to check the recommended tyre pressure for your car. You can find this information in your vehicle's owner's manual or on a sticker inside the driver's side door. Using the tyre pressure gauge, check the pressure in all four tyres.

If the pressure is too low, attach the air compressor to the tyre valve and add air until the pressure reaches the recommended level. If the pressure is too high, use the gauge to release some air until the tyre pressure is correct. Once you've checked and adjusted all four tyres, don't forget to screw the valve caps back on tightly.

Find Tyres

The bottom line is that if you ever see your tyre pressure warning light come on, don't panic. It's quite common and can be caused by various reasons, including changes in temperature, punctured or damaged tyres, or simply needing to top up your tyres with air.

The important thing is to act quickly and take care of the issue before it becomes a safety hazard on the road. And if you do need new tyres, don't worry; we've got you covered.

As a leading online tyre comparison tool, we make it easy for you to find the perfect tyres for your vehicle, whether you need replacements for damaged ones or simply want to modify and upgrade your pride and joy. Start browsing our car tyre selection today.