UNDERSTANDING YOUR CAR’S TPMS
If your car was manufactured in 2007 or later, it should have a Tire Pressure Monitoring System (TPMS). There are two types of systems: indirect and direct. Direct, the more common system today, uses sensors placed inside each wheel to provide precise real-time air pressure readings. An indirect system works with the Anti-lock Brake System to monitor if an underinflated tire causes one wheel to rotate faster than the others when driving straight down the road. Understanding your TPMS, including checking your TPMS system and performing necessary maintenance like TPMS sensor replacement, is an important part of maintaining your vehicle and staying safe on the road.
IF YOUR TIRES ARE NOT PROPERLY INFLATED, YOU COULD BE RISKING:
- Your safety. Underinflated tires may cause increased tire friction and overheating which could be dangerous.
- Your tire performance. Underinflated tires can lose traction and responsiveness in all weather conditions.
- Lower fuel economy. Underinflated tires make your vehicle work harder and use more fuel.
- Increased tire wear. Underinflated tires can wear out your tires faster.
If your TPMS light blinks 3-5 times and then turns solid, your system is malfunctioning and requires some type of service. If your TPMS light illuminates and remains solid, the pressure inside one or more tires is not matching up with the manufacturer’s recommendations. You can find the recommended tire pressure on the tire placard sticker, which is usually located on the driver’s side door jamb, the gas tank door, or in the owners manual.
HOW OUR TPMS REPAIR SERVICES WORK
Frequently Asked Questions
PSI (pounds per square inch) is a unit of measurement used to determine recommended tire pressure levels. Your vehicle’s recommended PSI is listed in the owner’s manual as well as on a sticker located on the door jamb, glove box door, fuel door, or spare tire. These numbers reflect the PSI needed for proper load support and safe handling. Many vehicles also require different levels for the front and rear tires, so use a tire pressure gauge to adjust as needed.
Tire pressure shifts with temperature because air contracts in the cold and expands in the heat, so it’s important to check pressure during weather changes. Tires typically lose or gain 1 to 2 PSI for every 10 degrees Fahrenheit, which means a sudden cold snap or warm spell can change levels by several PSI. Cold weather may also cause temporary drops that return once temperatures rise, while hot weather can increase PSI throughout the day.
A tire pressure monitoring system (TPMS) alerts you when a tire is significantly underinflated, using either direct sensors inside each tire or indirect readings from the anti-lock braking system (ABS) wheel-speed system. When pressure drops below the recommended PSI, the TPMS light appears on the dashboard, typically as a yellow horseshoe-shaped tire with an exclamation point. Some vehicles may also display an icon identifying which tire is low. If the light stays on, confirm pressure with a gauge and inflate the affected tire to the recommended PSI. Persistent warnings may indicate a puncture, slow leak, or sensor issue that requires diagnostic testing.
Checking and filling your tires starts with finding the recommended PSI on the driver's door jamb or in the owner’s manual. Then, use a tire pressure gauge to get an accurate reading. Remove the valve stem cap, press the gauge firmly onto the valve, and compare the reading to the cold tire specification. If pressure is low, add air at a gas station or with a home compressor in short bursts, checking frequently to avoid overinflating. Release excess air if needed, then replace the valve caps once all tires reach the proper level. If you need assistance with filling tires, make an appointment at your nearest Firestone Complete Auto Care for in-person guidance.
Incorrect tire pressure can affect fuel economy, handling, braking, and tire lifespan. Underinflated tires create more surface contact with the road, which can make the vehicle feel less responsive and reduce fuel efficiency. The U.S. Department of Energy reports that gas mileage can drop by about 0.2 percent for every 1 PSI decrease in average pressure. Underinflation also accelerates wear and increases the risk of damage. Overinflated tires have less road contact, which can lead to uneven wear, reduced braking performance, and greater susceptibility to potholes or debris. Regular gauge checks help keep tires at the recommended PSI for safe operation.