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What Does TPMS Mean?

Posted by Auto.com Staff | Jan 3, 2019

TPMS stands for Tire Pressure Monitoring System. If you drive a newer car, there is a good chance your car is equipped with one. Having a tire pressure monitoring system can take a lot of the guesswork out of wondering whether or not your tires are holding the right amount of pressure. But you may wonder, how does the TPMS work, and why is it a thing?

There are two types of TPMS sensors. With the direct TMPS sensor, a special sensor is mounted on the wheel inside your tire. This sensor feeds information directly to your car so that the TPMS can alert you when the tire pressure is too far out of spec.

The second type is known as an indirect TPMS because the sensor actually calculates tire pressure through the rotational speed of the tires. This system is connected to your car's antilock brake system. If tire pressure changes in one tire, then it will rotate at a slightly different speed than the rest of the tires, and your TPMS will send a signal that causes the TPMS light to come on.

When your TPMS light comes on and stays solid, that means one of your tires is over- or under-inflated.  Having too much air pressure in a tire can affect treadwear and vehicle handling. It can also lead to premature wear and tear on the tire. On the other hand, if your tire is underinflated, it can cause safety issues with the handling of the car and cause the belts in the tires to break down. Both overinflation and underinflation can cause catastrophic tire failure. If you see your TPMS light come on, drive to a safe place where you can visually inspect the tires.

Sometimes, you may see the TPMS icon on your dashboard start flashing. This means there is an issue with the sensor itself, and you should schedule an appointment with wherever you take your vehicles for repairs. While the TPMS on your car should never completely replace regular tire pressure checks, having the system in good working order can save you trouble in the event that something happens to your tires while you are driving.