Tyres
Tyre warning light in winter: why pressure can change
Cold weather can lower tyre pressure. Check the tyres when cold and adjust them to the manufacturer’s figures.
As temperatures fall, tyre pressure can drop and trigger the TPMS. Stop safely, check all wheels when cold and use the manufacturer’s figures; if a tyre is damaged or losing air, seek assistance.
Why cold weather changes the reading
Tyre air pressure varies with temperature. A seasonal drop can take a tyre below the monitoring system’s threshold, but the warning light alone cannot tell you whether the cause is simply cold weather or a puncture.
Do not turn off the warning without checking. Slow down gradually and stop somewhere safe; inspect all four tyres for visible damage or signs of a leak. If a wheel is visibly flat, the vehicle vibrates or pulls to one side, do not continue at normal speed.
Measure when the tyres are cold
Read the recommended figure in the handbook or on the vehicle’s label. Check the tyres before setting off or after the car has been parked long enough to cool; driving warms them and raises the reading. Use the pressure specified for the load if you are travelling with passengers and luggage.
Do not add a standard amount of air just because it is winter: the correct figure differs between cars. Inflate only to the pressure specified for your model and check the spare as well. If the warning returns soon afterwards, have a leak or faulty valve investigated.
Reset the system correctly
After correcting the pressure, check the handbook to see whether the car needs a TPMS reset or updates its reference automatically. A reset does not repair a tyre and must not be used to clear a warning before checking. If a sensor fault message appears, book a garage inspection.
Check your tyres when the seasons change and before a journey, not only when the warning light comes on. Keep valve caps and valves in good condition and check tread wear. Correct pressure does not make a damaged tyre safe, resolve an unsuitable winter tyre or make driving too fast on cold, wet roads safe.
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Frequently asked questions
Is cold weather always the cause of the warning?
No. Temperature can lower pressure, but the warning may also point to a leak or a system fault. Inspect the tyres and measure all four before blaming the weather.
Should I increase tyre pressure in winter?
Follow the manufacturer’s figure for your vehicle and load. Do not apply a universal increase; if the warning persists after adjustment, have the tyre and TPMS checked.