Jack Williams

Is Your TPMS Working? Do you Know What it is?

If you own a car made in 2007 or later, you probably don't check your tire pressure unless you receive a dashboard warning from your tire pressure monitoring system, or TPMS.

TPMS has been required on every new vehicle sold in the United States since 2008 and has been credited with halving the incidence of underinflated tires--with obvious ramifications for driver safety--in vehicles on our roadways.

Your TPMS should activate your low-tire-pressure warning light if any of your tires is at least 25 percent below its proper inflation level. But what if your TPMS isn't working correctly?

The TPMS relies on sensors mounted in either the braking system, or, in higher end vehicles, inside the tires themselves. Like anything else in your car, these sensors are susceptible to damage. Potholes and curb impacts have the potential to knock them out of commission, and inexperienced auto repair technicians have been known to damage them during tire or brake service without realizing it. Some repair shops have reported incidents of internal TPMS sensors being damaged through the use canned tire inflator products, such as "Fix-A-Flat."

Even if your TPMS sensors are undamaged, the sensors are powered by non-replaceable batteries that typically last between five and ten years. When the battery dies, the sensor has to be replaced. A new TPMS sensor costs about $100. Ask your qualified service technician to inspect your TPMS sensors at your next service visit.