What is TPMS?
TPMS stands for Tire Pressure Monitoring System. It’s a safety system built into your vehicle (or retrofitted) that monitors your tire pressure, and alerts you when the pressure in one or more tires falls to an unacceptable level.
Why are underinflated tires such a big deal?
Underinflated tires are susceptible to a variety of problems, from mild (premature wear and increased fuel consumption) to major (tire failure, including tread separation and blowouts). According to Schrader, a leading manufacturer of tire pressure monitoring systems, underinflated tires wreak a staggering amount of havoc on our nation’s roads and highways, contributing to 250,000 crashes, 33,000 injuries, and 660 deaths every year.¹ TPMS can have a huge impact on these sobering statistics. The U.S. government believes that once all vehicles are equipped with TPMS, as many as 120 fatalities and 8,500 crash-related injuries could be prevented each year.²
And there are even more benefits to TPMS. Schrader tells us that underinflated tires waste 3.5 million gallons of gas every single day.³ That’s fuel that could be saved (and money that could stay in drivers’ wallets) if tires were properly inflated. An uninflated tire will also wear more quickly, which can cost you money because the tire may need to be replaced earlier than expected.
History of TPMS
TPMS originated on European luxury cars in the 1980s; the first American car equipped with TPMS was the 1997 Chevrolet Corvette. TPMS got its big break in 2000, when the Clinton Administration enacted the TREAD (Transportation Recall Enhancement Accountability and Documentation) Act. Among other transportation safety improvements, the TREAD Act mandated that every new car sold in the United States after September 2007 be equipped with TPMS.
How do I know if I have TPMS?
Most passenger cars and light trucks model year 2008 or newer have tire pressure monitoring systems.
If your vehicle is TPMS-equipped, a warning light or other display will alert you when one or more of your tires falls below its recommended pressure, as stated on the vehicle’s door jamb placard. Here are a few examples of these displays:
There are also aftermarket TPMS systems, which usually have a display that mounts on the vehicle’s dashboard.
I have TPMS — do I still need to check my tire pressure?
Yes. Even with TPMS, it’s still important to check your tire pressure regularly because many systems won’t alert you until a tire is 25% or more below its recommended inflation pressure. The sooner you catch an underinflated tire and return it to the correct pressure, the better.
How do I get my TPMS serviced?
Rebuilding TPMS sensors
Servicing a vehicle’s TPMS requires special tools and training. In most cases, each wheel will have a TPMS sensor attached to the valve stem where the air is added. Between this stem and the wheel is a rubber grommet that seals the air inside the tire and protects the sensor from the elements.
Just like the rubber valve stem that was replaced at every tire change for years because the weather and other elements caused wear, the rubber grommet needs to be replaced, along with the nut that holds the stem and the nickel-plated valve core in the stem.
Moisture and corrosion eat away at the stem, which is why the caps have moisture seals to protect the internal components. To make sure you don’t create a leak when replacing the tires, all these components should be replaced (or in tire lingo, the TPMS sensor needs to be rebuilt). Your installer will generally charge a small additional fee for performing this service.
There may also be a small extra cost involved when rotating tires, because some vehicles require “relearning” of the position of each sensor after the tires have been moved. Each vehicle make and model has its own unique relearning procedure, so it takes special knowledge, equipment, and time for the technician to ensure that the system is working properly.
Replacing TPMS sensors
TPMS sensors will typically need to be replaced after 5 to 10 years of use, as the sealed batteries wear out. Timing varies due to use, weather conditions, and maintenance. New sensors have to be programmed into the vehicle’s onboard computer system with special equipment, and in most cases there is a charge for this service. Replacing sensors can be an expensive proposition (up to $200 per sensor in some cases), but we believe that the safety and savings benefits of TPMS far outweigh the cost.
1. Schrader, TPMS Made Simple, TPMS facts
2. Safercar.gov, TPMS