Symptoms
- TPMS light comes on when temperatures drop
- Tires look slightly more deflated on cold mornings
- Pressure returns to normal once it warms up
Likely causes
- CommonNormal air contraction in cold temperaturesThis is physics, not a leak, and affects all tires equally.
- PossibleAn existing slow leak made more noticeable by cold weatherA tire that was borderline low may dip below the warning threshold once it's cold.
What to do
- Check tire pressure when the car has been sitting for a few hours (cold), not right after driving.
- Compare to the door jamb sticker spec, which is meant for cold tires.
- Add air to reach the correct cold pressure; don't just wait for it to warm up if it's meaningfully low.
- Recheck weekly during cold snaps since pressure will keep shifting with temperature swings.
- If one tire consistently needs more air than the others, treat it as a possible slow leak and have it checked.
Tools and parts
- Tire pressure gauge
- Air compressor
When to call a pro
If pressure keeps dropping unevenly across tires, have a shop check for a leak rather than assuming it's just the cold.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.