What to do when the light comes on
- Look at the tires. If one is visibly flat or the car handles strangely, slow down and pull over somewhere safe. Don’t keep driving on a flat tire.
- Check all four with a gauge — and the spare if it has a sensor. You can’t judge pressure by eye. See how to check tire pressure.
- Inflate to the pressure on the sticker in the driver’s door jamb, not the maximum printed on the tire.
- Drive a few miles. The light usually goes off once the system sees the right pressure. Some cars need a reset — your manual explains how.
- If a tire keeps losing air, have it checked for a puncture or leaking valve.
Why the light comes on when it gets cold
Air contracts as it cools, so tire pressure drops when the temperature falls — roughly 1 psi for every 10°F. Tires that were borderline in autumn can trigger the light on the first cold morning. Top them up to the door-jamb pressure, checked when the tires are cold.
When the light is flashing
A flashing light points to a problem with the monitoring system rather than the pressure: a sensor battery that has run down, a damaged sensor, or a sensor that wasn’t set up after new tires or wheels were fitted. The system can’t warn you about low pressure until it’s fixed, so check pressures by hand in the meantime and have a tire shop diagnose it.
Common questions
Is it safe to drive with the tire pressure light on?
Only gently and far enough to reach air, and only if no tire is visibly flat. Low tires wear faster, handle worse and can overheat.
I filled the tires but the light is still on.
Drive for a few miles first. If it stays on, check whether your car needs a TPMS reset, and check the spare. If it’s flashing, the system needs service.
Does the light replace checking pressure myself?
No. It only warns when a tire is well below the right pressure. A monthly check keeps tires at the correct pressure, which helps them last — see how long tires last.