What You Should Know About the TPMS

Checking the Air Pressure of a Tire with a Tire-Pressure Gauge

All new cars and light trucks manufactured since 2008 come with a tire pressure monitoring system. Called the TPMS for short, this system monitors tire pressure and displays an alert if an under-inflated tire is detected. This is usually just an illuminated light on the dashboard, but some models may provide an audible alert as well.

Don’t Overlook the Importance of Proper Tire Pressure!

Are under-inflated tires really that big of a deal? The short answer is yes! First, it’s important to understand that tire pressure plays a large role in how your vehicle handles. If your tires aren’t inflated enough, they’re not likely to handle well—which can be dangerous. Second, under-inflated tires can overheat. This can cause the tire to come apart, which can also lead to accidents.

These reasons are why government regulations now require TPMS systems in all late-model vehicles. By alerting drivers about low tire pressure, TPMS systems reduce accidents and save lives. There are also some positive effects on the environment. Under-inflated tires waste fuel; you lose approximately 1% of your fuel economy for every 3 lbs. a tire is below its recommended pressure. So, not only can you save about a tank of fuel per year, but you can also look forward to not needing to replace your tires as often.

Two Types of TPMS

There are two types of TPMS systems in today’s vehicles: direct systems and indirect systems. Direct TPMS systems utilize sensors that monitor pressure within each tire. In some cases, they may even monitor tire temperature readings. This information is sent to a centralized control module, where it’s analyzed and interpreted. If the tire pressure is low, this data will be transmitted to the dashboard, and the indicator light will illuminate.

Indirect TPMS systems typically rely on wheel speed sensors used by the anti-lock brake system. These sensors measure the rate of each wheel’s revolution, which can then be used by the onboard computer system to compare with each of the wheels, as well as other types of vehicle operation data, like speed. Based on each wheel’s rate of revolution, the computer can interpret the relative size of the tires on your vehicle. If a wheel starts to revolve faster than it should, the computer determines that the wheel is under-inflated, which then triggers the TPMS warning light.

When Your TPMS Becomes Worn or Damaged…

Just like other systems in your vehicle, TPMS parts and components can wear out and become damaged over time. When this happens, they’ll need to be replaced. Many automakers use proprietary technology for these highly specialized systems, so you should always work with an experienced technician. It’s also important to remember to reset the system when you have your tires changed or rotated.

Since the TPMS system is so important to your safety, it’s always a good idea to make the necessary repairs as soon as possible. Keep in mind that although the TPMS is a great safety feature, it shouldn’t be a substitute for regular tire pressure checks. In many cases, these systems are designed to alert you once the tire pressure is below a certain level, but not as soon as the pressure is lower than the recommended amount. This means you could be driving on under-inflated tires for a while until the pressure gets low enough to trigger the warning light. Make sure to check your tire pressure once and month and refill them to your manufacturer’s recommended pressure as needed.

If you need TPMS repairs or other tire services, visit EuroCar Service in Seattle! Our ASE-certified technicians specialize in all European makes and models, including Audi, BMW, Mercedes, Jaguar, Land Rover, Volvo, Volkswagen, Saab, Mini-Cooper, Smart Car, and Fiat. Request an appointment online, or give us a call today at (206) 527-8828!