Tyre Pressure Warning Light On? What To Do

## That Tyre Light On Your Dashboard. What Does It Mean?

You're driving and a yellow light appears. It looks like a flat tyre with an exclamation mark, or sometimes just "TPMS".

That's your tyre pressure warning light. Your car is telling you something's wrong with your tyre pressure.

Here's what to do.

What The Tyre Pressure Light Means

Solid light: One or more tyres is significantly low on pressure. Usually more than 25% below recommended.

Flashing light: Usually indicates a fault with the TPMS (Tyre Pressure Monitoring System) itself, not necessarily a pressure problem.

Is It Safe To Drive?

Solid light, car feels normal: You can drive carefully to a petrol station or safe place to check pressure. Keep speeds low. Avoid motorways if possible.

Solid light, car feels different: Pull over safely and inspect the tyres. If one looks flat, don't drive on it.

Flashing light: Usually safe to continue, but get the system checked. Could be a sensor fault or battery issue.

Tyre visibly flat: Do not drive. You'll damage the tyre and wheel.

Step 1: Pull Over And Check

Find somewhere safe to stop. Walk around the car and visually inspect each tyre.

• **Look for:**
• Obvious flatness
• Bulges or damage
• Objects stuck in the tread (nails, screws)
• Uneven wear

If a tyre looks fine visually but the light is on, the pressure is probably just a bit low. You can drive carefully to a petrol station.

Step 2: Check And Adjust Pressure

Find a petrol station with an air pump (most have them).

Finding Your Correct Pressure The recommended pressure is NOT on the tyre itself. It's either: - Inside the driver's door frame (sticker) - In your owner's manual - Inside the fuel filler cap

Common pressures: Most cars run between 30-35 PSI. Don't guess — check your specific values.

Checking Pressure 1. Remove the valve cap 2. Attach the pressure gauge/pump 3. Read the current pressure 4. Add or remove air as needed 5. Replace the valve cap

Don't Forget The Spare If you have a spare tyre, check its pressure too. A flat spare is useless when you need it.

Step 3: Reset The Light (If Needed)

On most cars, the light resets automatically after driving a few miles at normal pressure.

• **If it doesn't reset:**
• Check all four tyres again (including the spare if monitored)
• Some cars need a manual reset (check your manual)
• There might be a TPMS reset button (often in the glovebox or centre console)
• The system might need a few minutes of driving

What Causes Low Tyre Pressure?

Temperature Changes Air contracts when cold. A 10°C temperature drop can reduce pressure by 1-2 PSI. This is why the light often appears on cold mornings.

Solution: Top up and check again when tyres are warm.

Slow Puncture A nail or screw in the tread can cause a slow leak. The tyre loses pressure over days or weeks.

Solution: Get it inspected. Slow punctures can often be repaired if they're in the tread.

Damaged Valve The valve stem can crack or corrode, causing leaks.

Solution: Replace the valve. Cheap and quick.

Bead Leak Where the tyre meets the rim can develop a leak, especially on older or corroded wheels.

Solution: Tyre needs removing and refitting, rim may need cleaning.

Faulty Sensor TPMS sensors have batteries that last 5-10 years. When they die, you get warnings.

Solution: Replace the sensor. Usually done when fitting new tyres.

Actual Flat Tyre Sometimes it really is a flat tyre from a large puncture or blowout.

Solution: Spare tyre, puncture repair kit, or call for help.

When The Light Comes On In Cold Weather

This is extremely common. Don't panic.

What's happening: Cold overnight temperatures lowered the pressure. The light triggered.

What to do: Check and top up the pressure. If it keeps happening (more than once), you might have a slow leak.

Prevention: Check pressure monthly and keep tyres slightly above minimum, especially in winter.

TPMS Types And Behaviour

Direct TPMS Has sensors in each wheel that measure actual pressure. More accurate but sensors can fail.

Light behaviour: Tells you exactly which tyre is low (on dashboard or via buttons).

Indirect TPMS Uses ABS sensors to detect rotation speed differences. No pressure sensors to fail.

Light behaviour: Knows pressure is low but not which tyre. Must check all four.

Can Low Pressure Damage Tyres?

• **Yes.** Driving on underinflated tyres causes:
• Increased wear on outer edges
• Higher fuel consumption
• Poor handling
• Risk of blowouts (flexing generates heat)
• Potential wheel damage

Never drive far on a significantly low tyre. Top it up at the nearest opportunity.

When To Replace vs Repair

• **Repair possible if:**
• Puncture is in the tread area
• Hole is smaller than 6mm
• Tyre is otherwise in good condition

• **Replace necessary if:**
• Damage is on the sidewall
• Puncture is too large
• Tyre has been driven flat (internal damage)
• Tyre is old or worn

How Much Does TPMS Cost?

Air top-up: Free at most petrol stations (some charge 20-50p) Puncture repair: £20-40 New TPMS sensor: £50-100 per wheel (fitted) New tyre: £50-150+ depending on size and brand

Get Help With Tyre Problems

Not sure what's wrong? Tyre looks flat?

Download Hault. A mobile mechanic can come to you, inspect the tyre, repair punctures on the spot, or fit a spare.

No driving on a dodgy tyre. No waiting at a tyre shop. Just help where you are.