Check TPMS is a warning that your tire pressure monitoring system has detected a problem with one or more tires
When the "Check TPMS" light appears on your dashboard, your vehicle is telling you that the tire pressure monitoring system — a network of sensors in or on your tires — has found that at least one tire is underinflated, overinflated, or the sensor itself is malfunctioning. This is not a suggestion to check your tires when you have time. It is a direct signal that something needs attention now.
The TPMS became mandatory on all new cars sold in the United States starting in 2008, following federal safety regulations. The system monitors the air pressure in each tire and alerts you when pressure drops below or rises above safe operating ranges. Most commonly, the light means one or more tires have lost air pressure — often because of a slow leak, temperature change, or a puncture.
The warning light itself is usually a yellow or amber symbol shaped like a tire with an exclamation mark inside it. Some vehicles also display a message on the instrument cluster that says "Check TPMS" or "Tire Pressure Low." On newer cars, you may see which specific tire is affected.
Key Takeaways
- A TPMS warning means at least one tire has pressure outside the safe range, most often too low.
- Check your tire pressures with a manual gauge and inflate to the pressure listed on the driver's door jamb, not the maximum pressure on the tire sidewall.
- Temperature drops of 10 degrees Fahrenheit or more can trigger the light even if your tires were fine the day before.
- If the light stays on after you inflate all tires to the correct pressure, a sensor may be faulty or a tire may have a slow leak.
- Driving on underinflated tires reduces fuel economy, causes uneven wear, and increases the risk of a blowout.
Why the light comes on: the most common causes
Low tire pressure is the reason behind roughly 80 percent of TPMS warnings. Tires naturally lose air over time — typically 1 to 2 pounds per square inch (PSI) per month — and the loss accelerates when temperatures drop. A 10-degree Fahrenheit temperature decrease can lower tire pressure by 1 to 2 PSI on its own, which is why the light often appears in fall or winter even if your tires were fine weeks earlier.
A puncture, valve stem leak, or slow leak from a damaged tire wall will also trigger the warning. These leaks may not be obvious — you might not see a nail or feel the tire going flat — but the sensor will detect the pressure drop. Overinflation is less common but can happen if you fill your tires on a hot day or use a gas station air pump that malfunctions.
A faulty sensor is the third major cause. TPMS sensors have batteries that last roughly 5 to 10 years, and when a battery dies or the sensor itself fails, the system cannot read that tire's pressure and triggers a warning. A sensor may also fail after a tire is replaced if the new tire was not fitted with a functioning sensor or if the sensor was damaged during installation.
How to check your tire pressure correctly
The correct tire pressure for your vehicle is not the number printed on the tire sidewall. That number — often 44 PSI or higher — is the maximum pressure the tire can safely hold, not the pressure your car needs. The correct pressure is listed on a sticker inside the driver's door jamb, on the fuel door, or in your owner's manual. Write this number down before you start.
Buy or borrow a tire pressure gauge — digital gauges are inexpensive and more accurate than stick gauges. Check the pressure in all four tires when they are cold, meaning the car has been parked for at least three hours and has not been driven in the heat. Tire pressure rises as tires warm up from driving, so a "hot" reading will be higher than the true pressure and may mask a problem.
If any tire is below the recommended pressure, use an air compressor at a gas station or tire shop to inflate it to the correct PSI. If a tire is overinflated, press the valve stem with a small tool to release air until the pressure is correct. After inflating all tires, drive for a few minutes and check whether the warning light turns off. If it does, the problem was low pressure and you are done.
What to do if the light stays on after you inflate your tires
If all four tires are at the correct pressure and the TPMS light is still on, one of two things is happening: a tire has a slow leak that will need repair, or a sensor has failed and will need replacement.
To narrow this down, check your tire pressures again the next day without driving the car. If one tire has lost 2 or more PSI overnight, it has a leak. Take that tire to a tire shop for inspection — they can patch a small puncture or, if the damage is too large or in the sidewall, replace the tire. If all tires hold their pressure but the light remains on, a sensor is likely faulty.
A faulty TPMS sensor costs between $150 and $250 to replace at a dealership or independent shop, depending on the vehicle and whether the sensor is in the tire valve stem or mounted on the wheel rim. Some shops can reprogram the system after replacement; others cannot, so ask before you commit. If your vehicle is still under warranty, the sensor replacement may be covered.
Temperature changes and seasonal TPMS warnings
The most predictable time for TPMS warnings is the transition from fall to winter. As outdoor temperature drops, the air inside your tires contracts, lowering pressure. A tire that was at 32 PSI in September may drop to 30 PSI in November without any leak. Because most vehicles are set to alert you when pressure falls 25 percent below the recommended level, a tire that was already slightly low in the fall will cross that threshold in the winter.
The reverse happens in spring. As temperatures warm, tire pressure rises, and the light may turn off on its own even if you did nothing. This is normal and not a sign that the problem has resolved — it is straightforward the effect of temperature on the air inside the tire.
To avoid seasonal warnings, check your tire pressure at the start of fall and again at the start of spring. Inflate to the recommended pressure when temperatures are mild, and you will have a buffer against both cold and warm swings.
How TPMS sensors work and why they fail
There are two types of TPMS systems: direct and indirect. A direct TPMS uses a sensor mounted inside each tire (usually in the valve stem) that measures pressure and transmits the reading wirelessly to the car's computer. An indirect TPMS uses the car's existing wheel speed sensors (part of the anti-lock brake system) to infer tire pressure by comparing how fast each wheel is spinning — an underinflated tire has a slightly smaller diameter and spins faster.
Direct TPMS is more accurate and is standard on most vehicles made after 2010. The sensors run on small batteries that typically last 5 to 10 years. When a battery dies, the sensor stops transmitting, and the system cannot read that tire's pressure. The warning light comes on and stays on until the sensor is replaced.
Sensors can also fail if they are damaged during a tire replacement, corroded by road salt, or struck by road debris. If you have recently had a tire replaced and the TPMS light came on shortly after, ask the shop whether they replaced the sensor or reused the old one. If they reused it and it was damaged during removal, that is likely the cause.
Driving with the TPMS light on: risks and what you should do
Driving with underinflated tires — the most common reason for a TPMS warning — carries real safety and cost consequences. Underinflated tires generate more heat, wear faster on the edges, and are more prone to blowouts, especially at highway speeds or when carrying a heavy load. Fuel economy also drops noticeably; a tire that is 10 PSI below the recommended pressure can reduce fuel economy by 3 to 5 percent.
If the TPMS light is on because of low pressure, do not ignore it for more than a few days. Check and inflate your tires as soon as you can. If the light is on because of a faulty sensor, there is no when ready safety risk — your tires are fine — but you have lost the ability to detect a real pressure problem in the future. Schedule a sensor replacement within a few weeks.
If you are unsure whether the problem is low pressure or a faulty sensor, the safest approach is to check your tire pressures when ready. This takes 10 minutes and costs nothing. If all tires are correct and the light is still on, you know a sensor needs attention but there is no emergency.
Frequently Asked Questions
Can I drive with the TPMS light on?
Yes, but only if you have confirmed that all tires are at the correct pressure. If the light is on because of low pressure, driving for extended distances or at highway speeds increases the risk of a blowout. If the light is on because of a faulty sensor, there is no when ready danger, but you should have the sensor replaced within a few weeks so you can detect real pressure problems in the future.
Will the TPMS light turn off on its own?
It will turn off if the underlying problem resolves. If low pressure caused the warning, inflating the tire will turn off the light within a few minutes of driving. If temperature was the cause, the light may turn off as temperatures warm. If a sensor failed, the light will stay on until the sensor is replaced.
What is the difference between the TPMS light and the tire pressure warning light?
They are the same thing. Different manufacturers use different names — some call it "Check TPMS," others call it "Tire Pressure Low" or show a tire symbol with an exclamation mark — but they all mean the tire pressure monitoring system has detected a problem.
Do I need to replace all four TPMS sensors at once?
No. You only need to replace the sensor that has failed. However, if all four sensors are the same age and near the end of their battery life, some shops recommend replacing all four at once to avoid multiple warnings over the next year or two. Ask your shop for their recommendation based on your vehicle's age.
Can I ignore the TPMS light if I know my tires are fine?
If you have checked all four tires with a gauge and confirmed they are at the correct pressure, then a faulty sensor is the cause and there is no safety issue. However, you should still have the sensor replaced so that the system can alert you to real pressure problems in the future. Ignoring the light means you lose an important safety tool.