Posted on 10/31/2025
Your tire pressure monitoring system (TPMS) is supposed to help you stay safe by alerting you when a tire is underinflated. But what if the warning light comes on and your tire pressure is perfectly fine? It’s not uncommon for drivers to see that TPMS warning and check their tires, only to find everything looks normal. So what’s going on? The answer might be that your sensor isn’t telling the whole truth. Let’s look at how this system works, what can cause it to give false warnings, and how to tell when it's the sensor, not the tire, that’s the real issue. What Does the TPMS Actually Monitor Most modern vehicles are equipped with direct TPMS. This type uses a pressure sensor mounted inside each wheel, typically as part of the valve stem. These sensors measure the actual air pressure in the tire and send that data to the car’s computer. When one or more tires drop below a certain threshold, usually around 25 percent below the r ... read more