If you are among the 42 percent of motorists who don’t know, this is the warning light for your vehicle’s tire pressure monitoring system (TPMS). When it comes on, one or more of your tires is dangerously underinflated and should be checked as soon as possible.
TPMS systems are standard on 2008 and newer cars, but many people are still unfamiliar with them. That can create a dangerous situation since under-inflated tires degrade vehicle handling, lengthen stopping distances, increase tire wear, waste gas and increase emissions. In extreme cases, underinflated tires can overheat to the point where they blow out. U.S. government studies indicate tire-related issues cause around 11,000 crashes and 200 fatalities each year.
All tires leak small amounts of air over time, and tire pressures also drop when outside temperatures decrease in fall and winter. Don’t wait for a TPMS warning light to act; check your tire pressures at least every month for maximum driving safety.
Proper inflation is a significant factor in preventing tire-related crashes, which is why the National Highway Traffic Safety Administration has required tire pressure monitoring systems (TPMS) on all new cars and light trucks since the 2008 model year.
By 2014, an estimated 104 million U.S. cars and light trucks had TPMS. However, a recent study found more than 4 in 10 U.S. drivers could not identify the dashboard warning light. The icon may be a yellow cross-section of a tire with an exclamation point inside, or a top view of a car with the low tire(s) highlighted.
Here’s what you need to know about this potentially life-saving system:
1. TPMS measure wheel rotation rates or monitor tire pressure directly to determine when one or more tires have lost pressure.
2. TPMS illuminate a warning icon on the instrument panel if the pressure in any tire falls more than 25 percent below the automaker’s specification.
3. TPMS work. A study found just 5.7 percent of 2008-2011 vehicles with the systems had one or more severely underinflated tires, compared to 23.1 percent of 2003-2007 cars without TPMS.
4. TPMS sensors that measure pressure directly contain batteries that last 6 to 10 years, after which the sensors must be replaced at a cost ranging from $150 to $600 per set.
5. TPMS warn when a tire is severely underinflated, but any pressure below specifications can cause problems. Don’t wait for the system to alert you. Check your tire pressures at least once a month.
Additional information regarding AAA's recommendations for proper vehicle maintenance is available on the AAA Newsroom and AAA's YouTube channel.
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