Tire Pressure Safety and Monitoring: A Closer Look at TPMS Systems

Car technology has come a long way, but some things remain unchanged, for example the fundamental laws of physics, particularly regarding friction between tires and the road, remain crucial in determining vehicle handling and stopping capabilities. Proper tire pressure plays a key part in overall tire performance. Incorrect tire pressure not only adversely affects vehicle dynamics and fuel efficiency but can pose serious safety risks, including the potential for a tire blowout leading to a severe crash.

Early Days of Tire Safety

Back in the 1970s, people started thinking about a way to warn drivers about low tire pressure. The National Highway Traffic Safety Administration (NHTSA) thought about a "low tire pressure warning" light, but the only option then was too expensive. The first Tire Pressure Monitoring System (TPMS) appeared in 1989 on the Chevrolet Corvette. Over time, TPMS became a standard or optional feature in many cars.

TREAD Act and TPMS Rules

In 2000, Congress passed the Tire Recall Enhancement, Accountability, and Documentation (TREAD) Act because of rollover crashes involving Ford Explorers in the 1990s. Section 13 of this act made it mandatory for new cars to have a system that warns drivers when a tire is significantly underinflated. Starting in 2008, TPMS systems became mandated in all cars under 10,000 pounds Gross Vehicle Weight Rating (GVWR). This was a crucial step in making vehicles safer and preventing accidents caused by underinflated tires.

AAA's Evaluation Study on TPMS

In the context of ongoing research projects, AAA evaluated the accuracy of TPMS systems in various 2022 and 2023 model year light vehicles. These assessments aim to ensure that TPMS technology continues to meet the standards set by regulatory mandates and contributes to the safe operation of vehicles on the road.

AAA conducted a series of tests on tire pressure monitoring systems (TPMS) in various vehicles to assess their effectiveness in detecting underinflated tires. Here's a summary of the key findings and recommendations:

• Eleven cars were tested, and when the tire pressure dropped to 75 percent of what's recommended, five cars showed a warning. Also, when the left front tire was deflated by 0.8-2.9 psi, five out of six cars lit up the warning light. TPMS seems to work well, but one car, the 2022 Ford F-250, didn't show a warning even when a tire was only 65 percent inflated. However, this car is at the upper limit for weight requirements for TPMS systems.
• Overall, TPMS worked well in showing accurate tire pressures when tested. It usually warned drivers when the pressure was 75 percent of what's recommended. However, one car, the 2022 Ford F-250 didn't show a warning even when a tire was only 65 percent inflated. It is worth noting that this vehicle is at the upper limit for weight requirements of TPMS systems.

Recommendations for Drivers

1. TPMS lights are designed to illuminate only when one or more tires are severely underinflated. Drivers are advised to regularly check the displayed tire pressure at each corner and maintain tires inflated to the labeled pressure specified on the driver’s door sill. (Note: If the tire sensor is blinking, it indicates that the TPMS system is malfunctioning and requires service and may need to be replaced.)
2. Even with TPMS, drivers should visually inspect their tires periodically for signs of damage to the tread surface and sidewall. (Note: Cold weather may cause false readings that cause the light to illuminate. Also, a nail in the tire or other puncture will cause the light to go on.)
3. Although displayed tire pressures were generally accurate, drivers should consider using a handheld gauge to periodically verify the proper operation of the TPMS system.

While TPMS is effective at warning about low tire pressure, regular visual inspections and periodic checks with a handheld gauge are recommended for optimal tire health and vehicle safety. This study reminds us that staying safe on the road is a combination of technology and good habits.