Why Does My Tire Pressure Light Come on When It’s Cold?

The dreaded “low tire pressure” warning light (often depicted as a graphic of a horseshoe with an exclamation point in the centre!) is undoubtedly something you’ve experienced if your automobile has a tire pressure monitoring system (TPMS). When it gets frigid, notifications frequently increase suddenly for drivers. What’s up with this bothersome and frequently inconvenient event, you might be asking yourself? And should I fill up my tires?

According to Rich White, executive director of the Car Care Council, “tire pressure reduces by 1-2 PSI for every 10 degrees reduction in temperature.” The unit of measurement for pressure is called PSI, or pounds per square inch. “In general, cold shrinks and warm expands. At this time of year, drivers frequently receive TPMS warnings and become concerned about their tires.” Due to the cold, the volume of the air is really decreasing in this situation. Less air equals less fully inflated tires, so to speak.

Just because something happens frequently doesn’t imply you should disregard it. “It’s usually chilly in the morning when people see this [light]. The light may go off when the temperature rises, but it’s possible that the tires will still be a few PSI underinflated “Black adds.

According to Jason Lancaster, an auto specialist and the creator of the website AccurateAutoAdvice, the TPMS continuously checks the air pressure using tiny sensors inside the air stems of the tires.

He claims through email that these systems, despite their best efforts, are not always completely accurate and can be wrong by as much as 2 PSI.

He cautions against doing so even if it may be easy to ignore the blinking light and continue on your path. He advises performing a rapid tire pressure check when the tire pressure alert appears, noting that digital tire gauges are significantly more accurate than those offered at many gas stations. “You can disregard the light if your gauge indicates that you have 32 PSI in each tire, or if you are within 1 PSI of that reading. Having said that, if you haven’t checked your tires’ pressure, it would be stupid to ignore the light. It’s always a good idea to inspect your tires because you can very well have one with a hole in it.”

If you add air and the issue still exists, get the tire calibrated by a mechanic or tire shop. And to maintain tire health and detect issues early, check your tires each month. The morning or after your car hasn’t been driven for a few hours are the finest times to accomplish this. For the most precise reading, the tires must be “cold.” Uncertain of how to gauge tire pressure? Visit the DMV’s detailed instructions.

There are a few things you can do, according to Lancaster, to stop the light from appearing in the first place:

  • You can overinflate your tires by 2 or 3 PSI, for instance, to 35 PSI, instead of the recommended 32 PSI. “The downside to overinflation like this is that your tires will wear a little faster — and your car will ride a little rougher — but the difference is negligible. Personally, this is my solution to this problem,” he says.
  • You can also inflate your tires with nitrogen instead of regular old air. “Nitrogen doesn’t expand or contract as readily as normal air, and the nitrogen machines also ‘dry’ the nitrogen so there’s no water vapor inside the tire. It’s the water vapor that causes the big pressure drops,” Lancaster says. “Most tire shops offer nitrogen inflation during install, so you have to opt for it at the time you buy.”

According to Jason Lancaster of AccurateAutoAdvice, the Ford-Firestone tire incident, in which low tire pressure caused Ford Explorers to roll over, is what gave rise to the TPMS (tire pressure monitoring system). “The National Highway Transportation Safety Administration mandated tire pressure monitoring systems for all new vehicles as one of its regulations. Sadly, the systems are glitchy “He claims.

Scroll to Top