Tyre Pressure Warning Light On? Do This Now.

What Is the Tyre Pressure Warning Light?

The tyre pressure warning light — officially called the Tyre Pressure Monitoring System (TPMS) light — is a horseshoe-shaped symbol with an exclamation mark, illuminated in amber. When it comes on, it means one or more of your tyres has dropped significantly below the recommended pressure — typically by 25% or more.

All new cars sold in the EU and UK since 2014 are required to have TPMS fitted. Many older vehicles have it too. It is there for a very good reason: under-inflated tyres are the leading cause of tyre failure and a major contributor to accidents.

What to Do Immediately When the TPMS Light Comes On

Step 1: Don't Panic, But Don't Ignore It

The light doesn't necessarily mean you have a puncture — it may be a gradual pressure loss or a cold weather pressure drop. But it does mean you need to act soon. Don't continue driving indefinitely without checking.

Step 2: Find a Safe Place to Stop

Pull over at the next safe opportunity — a car park, lay-by, or petrol station. Do not stop on a motorway or in a dangerous location unless the tyre has clearly failed (in which case, follow blowout procedure).

Step 3: Visually Inspect All Four Tyres

Walk around the car. Look for:

• An obviously flat or very low tyre
• Any visible damage — a nail, screw, or shard of metal sticking out of the tread
• Any sidewall damage or bulging

Step 4: Inflate the Tyres

If you can reach a petrol station, inflate all four tyres to the manufacturer-recommended pressures. These are usually found:

• On a sticker inside the driver's door frame or fuel cap flap
• In the vehicle handbook

Use the tyre inflation machines at petrol stations. Check all four tyres — the TPMS doesn't always tell you which specific tyre is low (unless you have a more advanced system that displays individual pressures).

Step 5: See If the Light Clears

After inflating to correct pressure, drive for a few minutes. The TPMS light should go off. If it remains on, one of the following applies:

• One tyre has a slow puncture and is losing air continuously
• A TPMS sensor is faulty
• You have not fully inflated all tyres to the correct pressure

Common Reasons the TPMS Light Comes On

Cold Weather Pressure Drop

Tyre pressure decreases by approximately 1 PSI for every 10°C drop in temperature. On a cold winter morning, all four tyres can drop below the threshold simultaneously. This is normal — inflate to correct pressure and the light will go off.

Slow Puncture

A small nail or screw in the tread can cause a slow puncture — losing a few PSI over days or weeks. The tyre may still look inflated visually but be significantly under-pressure. If you inflate and the light comes back on within a day or two, you almost certainly have a slow puncture.

Faulty TPMS Sensor

TPMS sensors have batteries that last 5–7 years typically. When the battery dies, the sensor can't transmit, and the warning light illuminates. This is a repair job for a tyre professional — TyreBlitz can replace TPMS sensors at your location.

Valve Leak

The tyre valve stem can degrade over time, causing a slow air leak. This is usually an inexpensive fix — the valve is replaced when a new tyre is fitted.

Can You Drive With the TPMS Light On?

For a short distance, to get to a safe place or petrol station — yes. Indefinitely — absolutely not. Driving significantly under-inflated causes rapid tyre degradation, poor fuel economy, impaired handling, and dramatically increases the risk of a blowout. Get it sorted the same day.

When to Call TyreBlitz

Call 0208 079 1031 if:

• The tyre is visibly flat or has obvious damage
• The TPMS light comes back on within 24 hours of inflating
• You've identified a nail or screw in the tread
• You can see a sidewall bulge or damage

We can come to your home, workplace, or roadside location. Slow punctures can often be repaired rather than replaced — we'll assess on arrival and advise honestly.