Unnoticed low tire pressure can result in tire damage and blowouts, which can result in the dangerous loss of vehicle control. To address this concern, Congress passed the TREAD Act in 2008, requiring tire-pressure monitoring systems
(TPMS) in all new passenger vehicles. TPMS is an electronic sensor system inside the tire that monitors air pressure. Most are attached to the base of the valve stem. Others may be attached by a band to the rim.
If tires become significantly underinflated, the TPMS activates a warning light on the vehicle’s dash. A steady light means the tire pressure needs to be addressed.
A flashing light means the TPMS needs checked, most often due to a low battery. Because few TPMS units are designed with replacement batteries, that means the entire TMPS sensor would need to be replaced.
When mounting new tires on a vehicle or rotating existing tires, it’s important for the technician to understand the type of TPMS technology in place, where it is located and how to recalibrate and reset the TPMS system. Check the vehicle owner’s guide or other quality service information resources.
For the TPMS system to indicate the correct position of the tire with low or high pressure, you have to reprogram the receiver after rotating the tires. If you don't do this, the system still will indicate the faulty pressure, but in the wrong position. Refer to the instructions in your operating manual and follow the procedure specified to reset the TPMS unit.
While you don’t need to replace TPMS sensors on new tires, it’s often convenient to do so, especially if the sensors are more than a few years old. Most sensor batteries last five to 10 years, so older sensors may not last long after the installation of new tires.