Just noticed the low tire pressure light glowing on your dash? Don’t panic! An active tire pressure light only means one of your tires is probably slightly underinflated, which, in most cases, is totally normal. Still, while the solution can sometimes be as simple as putting a little more air in a tire, in some other cases, you might need a bit more effort to properly reset the system and make the tire pressure warning light disappear.
Luckily, there’s no need to worry here; if you’re still having issues after inflating your tires to the proper psi, you’ve come to the right place!
Indeed, we’ll explain everything you need to know about your car’s Tire Pressure Monitoring System (TPMS), how the tire pressure light works, what triggers it, and what you should do to turn it off.
Let’s dig in!
Tire-Pressure Monitoring System Explained
The tire pressure light (TPMS light for short) is integral to most modern vehicles’ Tire Pressure Monitoring System (TPMS) and is designed to track the air pressure inside your tires and alert you if it falls way below the recommended PSI with a flashing tire pressure light. Another alternative may include a notification on the infotainment display telling you to service the tire monitoring system.
However, it’s important to mention that the TPMS is a relatively new feature in the industry, so not all vehicles were born with it. In fact, despite making its debut in the 1980s’ European luxury cars, TPMS only started becoming mandatory for all new vehicles sold in the US by the end of 2007.
TPMS Light On: Are You in Danger?
It’s ok; you can stay calm — a “low tire pressure light” is one of the least severe warning lights on your dash. Indeed, the typical culprit of tire pressure loss is either a small puncture or a sudden temperature drop, so they’re easily fixable and, in most cases, won’t cripple your car instantly. Even installing wheels without air pressure sensors can trigger the tire pressure light, which may happen to those who own multiple sets of wheels for different occasions, like off-roading or winter tires.
Regardless, you should pay attention to the TPMS when it’s trying to warn you of a tire issue. Driving with an underinflated tire has many drawbacks, including a lower fuel economy, poorer handling, faster tire wear, and increased risks of blowouts.
Nonetheless, a turned-on TPMS light is quite common on vehicles adopting this feature. Many carmakers even provided instructions on their websites and repair manuals on how to service tire monitor systems. A BMW repair manual, for instance, has a section containing multiple solutions to reset the low tire pressure light if you see it glowing on your digital driver’s display.
What To Do When the Tire Pressure Light Comes On?
When you see the TPMS light on, the first thing to do is check your tires. Start by taking out your tire gauge and make sure they are at the recommended pressure. If not, take out your tire inflator or drive to the nearest gas station/auto shop to inflate them to the recommended PSI (you’ll find it on the label inside the driver’s door or your car owner’s manual).
If you notice one of your tires seems significantly more deflated than others, check for stuck nails or similar sharp objects that may cause it to leak air. Ideally, you’ll want to mend a punctured tire before inflating it, so consider patching it first using a tire repair kit or installing your spare if your nearest tire shop is still a long drive away.
How to Reset the Tire Pressure Light
Usually, patching and reinflating your tires with the proper air pressure should do the trick, but sometimes that’s not enough to get rid of the tire pressure light. Consequently, you’ll need to take extra measures to reset it properly.
For older cars, a common method is to drive your vehicle at around 50 mph for roughly 10 minutes, which should help the TPMS light reset itself. Alternatively, some cars have a dedicated “TPMS reset” button. If this is your case, try turning on the car without starting the engine and hold the TPMS reset button until the warning light blinks three times — doing so will reset the system. Release the button and start the engine (you might need to wait as long as 20 minutes for the system to recalibrate and the low tire pressure light to go off.
On more modern vehicles released in the last 5-10 years, there is no physical TPMS reset button. Instead, you’ll need to go through the menu on the instrument cluster or center infotainment display (depending on the model). Search for TPMS or TPWS under the “Vehicle Settings” menu and reset the blinking tire pressure light (the software will guide you).
If those methods don’t work, try the following additional tricks — those are a bit more complicated and should be kept as a last resort.
First, inflate your tires 3 PSI higher than recommended, then deflate them completely and reinflate them to the recommended pressure. This should simulate a tire repair, causing the air pressure sensor to recalibrate itself and the system to reset.
And if that still won’t do, try disconnecting the positive battery cable when the car is off, turning the car on without starting the engine, then honking the horn for roughly three seconds to discharge any leftover power stored in the battery. Given your tires are properly inflated, the TPMS light should go off once you reconnect the battery and start the engine.
What Does a Blinking Tire Pressure Light Means?
When you notice the tire pressure light blinking, that could mean different things depending on how long it lasts. If the TPMS only flashes for a few seconds after starting your engine, that’s normal. Some vehicles do a bulb check at startups, which tends to make all the warning lights turn on for a few seconds, so you probably shouldn’t worry about it.
Meanwhile, if the blinking continues even after you start driving (and assuming your tires are properly inflated), it may indicate a tire pressure sensor fault or a weak sensor battery. In that case, you might be required to change the TPMS battery or replace the complete sensor.
Last Words
Having an issue with a blinking tire pressure light after you’ve done everything (mentioned in this article) to remedy it is somewhat rare and usually means something might be wrong with one of the sensors. Luckily, they are relatively inexpensive, ranging from $25 to $100, depending on the model. Unfortunately, replacing a TPMS sensor also requires removing the tire from the wheel to get to the sensor, which also means it will need to be rebalanced.
Moreover, the new sensor will need to be paired with the TPMS module, which will, in most cases, require specialized equipment and a quick visit to the nearest tire shop.
That being said, most TPMS issues should be cheap and quick to fix. And keeping in mind that driving on underinflated tires is not only rather unsafe but will also have a negative impact on your car’s fuel efficiency, it’s best to act on it immediately!
Every year when the temps drop below freezing my tire light goes on and stays on until spring. Using the reset routine does no good untill it warms up.
That could be two things:
1- When the temperature drops, the air inside the tire condenses and takes up less space, thus reducing the overall pressure. Expect tire pressure to normally decrease about 1 PSI for every 10 degrees — and that is absolutely normal. Try inflating your tires a couple PSIs above the manufacturer’s recommended threshold and you should be just fine.
2- If you live in a snowy climate and install winter tires on a different wheel set, your winter set probably doesn’t have TMPS sensors, hence why the TPMS light comes up.
Otherwise, there’s no real reason for sensors to work any differently in cold or hot weather.