Why the Tyre Pressure Light Comes On (and What to Do About It)
You’re driving along when a small yellow symbol lights up on your dashboard — the tyre pressure warning light. For many UK drivers, it’s a moment of confusion or panic. Does it mean a flat tyre? A puncture? Or just cold weather?
This guide explains what the tyre pressure light means, why it comes on, and what to do when it does.
What Is the Tyre Pressure Warning Light?
Since 2014, all new cars in the UK must be fitted with a Tyre Pressure Monitoring System (TPMS).
- The system measures the air pressure inside your tyres.
- If the pressure drops by 25% or more, the warning light comes on.
- The symbol looks like a horseshoe with an exclamation mark inside.
If you see it, don’t ignore it — driving with underinflated tyres is unsafe and illegal if they fall below the legal limit.
Common Reasons the Tyre Pressure Light Comes On
1. Low Tyre Pressure
The most common reason is simply that your tyres need air. This can happen naturally over time.
2. Sudden Temperature Drops
Cold weather can reduce tyre pressure by 1–2 psi overnight, triggering the light.
3. Puncture or Slow Leak
A nail, screw, or small tear can cause gradual pressure loss.
4. Faulty Tyre Pressure Sensor
If all tyres are correctly inflated but the light stays on, the TPMS sensor may need replacing.
5. Tyre Change or Rotation
If wheels have been swapped without resetting the TPMS, the system may give false alerts.
What to Do When the Tyre Pressure Light Appears
- Stop safely: Pull over and visually check your tyres.
- Use a gauge: Measure the PSI against your manufacturer’s recommendation.
- Inflate if low: Add air at a petrol station or using a home compressor.
- Look for damage: If you spot a nail, bulge, or flat, don’t drive — call for roadside assistance.
- Reset the TPMS: Some cars require you to manually reset the system after adjusting pressures.
Not sure of the exact figure for your car? Use our tyre pressure by registration tool to get accurate PSI instantly by entering your number plate
How to Reset the Tyre Pressure Light (TPMS Reset)
- Button reset: Many cars have a TPMS reset button (often near the steering column).
- Infotainment system: Some newer models allow resetting via the dashboard menu.
- Automatic reset: Certain cars reset automatically after driving at the correct pressure for 10–15 minutes.
Check your car manual for the exact procedure.
When to Replace Tyre Pressure Sensors
TPMS sensors usually last 5–10 years but can fail earlier. Signs of failure include:
- The warning light stays on despite the correct pressure.
- Inconsistent or no readings.
- Garage diagnostics show TPMS error.
Replacement costs in the UK range from £40–£70 per sensor.
Final Word
The tyre pressure light is your car’s way of warning you something isn’t right. Don’t ignore it — check your tyres, inflate to the right PSI, and reset the system if needed.
Not sure what pressure your car needs? Use a tyre pressure by registration tool or book a free tyre check at your local garage. TyreSavings.
FAQs: Tyre Pressure Warning Light in the UK
Q1: Is it safe to drive with the tyre pressure light on?
Only for a short distance if you’ve checked your tyres and they’re safe. Otherwise, it could risk a blowout.
Q2: Why does my tyre pressure light keep coming on in cold weather?
Air contracts in lower temperatures, reducing pressure. Inflate to the correct PSI to stop repeated warnings.
Q3: Do I need to reset the tyre pressure light after inflating the tyres?
Yes, in many cars. Check your manual for reset instructions.
Q4: Can I fail my MOT because of the tyre pressure light?
Yes — since 2012, a faulty TPMS is a minor defect, but if your tyres are underinflated below the legal limit, it can lead to MOT failure.