Low Tire Pressure Light: Why Its On and How to Fix

Imagine this – you are peacefully driving your vehicle and suddenly the low tire pressure light on your dashboard comes on. This tiny indicator can cause confusion or even panic, especially if you’re not sure what it signifies.

The low tire pressure light can illuminate if one or more of your tires has dropped below recommended air pressure. Low pressure can be due to damage to the tire, or natural tendency of tires to lose air. In fact, a tire will lose about one pound of air pressure per month. And additional pound for every 10-degree decrease in temperature.

Truth is, you may be shocked to find out that this low tire pressure light can mean a few different possibilities. The main culprits range from small things like weather changes or minor air leaks, to more significant issues such as damaged tires due to running over a nail, hitting a curb, or potholes.

Knowing why it’s lit up is the first step in understanding how essential maintaining proper tire pressure is when it comes to vehicle performance and safety.

So if you are seeing that low tire pressure warning light, don’t worry. Let’s jump into everything you need to know about the low tire pressure light and why its on. Then we will cover what to do about it.

What is the Low Tire Pressure Light and Why is it on?

The low tire pressure light, also known as the TPMS (Tire Pressure Monitoring System) warning light, is created to alert drivers when one or more tires have insufficient air pressure.

This warning system is vitally important because proper tire inflation is crucial for optimal vehicle handling, fuel efficiency, and overall safety.

In fact, cars started coming with tire pressure monitoring systems as early as the 2000s. The exact timeline varies by manufacturer and model, but TPMS became more prevalent in vehicles after the introduction of the TREAD Act in the United States.

However, some car manufacturers began incorporating TPMS into their vehicles before the legislation even took effect.

Truth be told, TPMS technology has evolved drastically over time. At first, TPMS systems were mounted inside each tire to measure tire pressures.

Eventually, indirect TPMS systems were developed that relied on the wheel speed sensors of the anti-lock braking system. This new system transferred tire pressure changes based on the rotational speed of the wheels.

Simply put, an indirect TPMS measures how fast your tires are rotating and sends signals to the computer that will trigger the low tire pressure light when something in the rotation seems amiss.

What Are The Reasons Why the Low Tire Pressure Light May Come On?

Believe it or not, drastic changes in temperature can have a significant impact on tire pressure. When the temperature decreases, the air inside the tire contracts, causing a decrease in tire pressure.

Likewise, hotter weather causes air inside the tire to expand, leading to a temporary increase in tire pressure. These fluctuations in temperature can activate the low tire pressure light, indicating the need for adjustment.

And of course, the main contributor to a loss in air pressure is tire damage. Damage such as leaks or punctures in the tires can cause air to escape. This results in decreased air pressure, triggering the low air pressure warning light.

Another possibility for the illuminated low tire pressure light is due to a malfunctioning TPMS. As with any electronic sensor, the TPMS may experience failures or defects, leading to inaccurate readings and false alerts.

When this happens, it’s important to address the issue as soon as possible to ensure proper monitoring of tire pressure. Fact is, a faulty TPMS sensor can be a real safety hazard.

Finally, inadequate tire inflation can contribute to rapid air loss and subsequently activate the TPMS. This is common when a vehicle sits for an extended period of time without being driven.

If tires are underinflated, they are more prone to losing air at a faster rate, and ultimately damage to the tire. This will trigger the low tire pressure light and indicate the need for air pressure adjustment.

From personal experience, it’s never a bad idea to regularly check the tire pressures every month or two. It not only helps extend the life of the tire, but also helps ensure your safety while driving.

Why You Should Never Ignore the TPMS Light

When that pesky low tire pressure light comes on, it’s time to head to the nearest gas station for some air.

Truth is, safety issues arise when tires are not properly inflated. Underinflated tires compromises your car’s stability, braking efficiency, and traction. Ultimately these conditions elevate the risk of accidents, especially on wet and slippery roads.

In addition to safety concerns, tire pressure also impacts fuel consumption. When tires are underinflated, they create higher rolling resistance, which forces the engine to work harder and consume more fuel.

This increased demand on the engine results in higher fuel consumption. Which is why maintaining proper tire pressure is not only crucial for safety, but also plays a role in fuel efficiency.

What Should You Do If the Low Tire Pressure Light Comes On?

Now that you know everything about the low tire pressure light, you can learn what actions need to be taken in such a situation.

First things first, don’t panic and stay calm. This is especially important if the light got triggered when you were driving.  

Next, inspect your tires for any damage. If you have noticed a puncture, it’s advised to consult a professional at the repair shop.

If the tires look okay, you can measure the tire pressure with a tire pressure gauge. Each vehicle has its own specifications for tire pressure, so make sure to check the indications in the owner’s manual.

You can also find the necessary information on your car’s door jamb sticker

If the pressure is too low, you should inflate the tire with an air pump. If you don’t have one, you can go to the gas station or a repair shop. Most of them provide free air.

Keep in mind, that in some cars the TPMS will not turn off right after you get the tires inflated. You can reset it by pressing and holding the TPMS reset button. The light might also automatically turn off once you drive for a couple of minutes at a certain speed.

After inflating the tires to the recommended pressure level, make sure to check them at least once a month and before long trips.

Why is my TPMS light on when my Tire Pressure is Fine?

The low tire pressure indicator light may illuminate regardless of your tire pressure being within the normal range. This is due to a TPMS malfunction. It’s best to consult a mechanic for a thorough inspection of the TPMS system.

Low Tire Pressure Light FAQs

How Can You Tell if a TPMS is Defective?

If your tires have low air pressure and you didn’t get a warning, it’s likely because of a faulty TPMS sensor. Use a tire pressure gauge to check if it’s the sensor or a tire causing the problem. You may also notice that the steering feels tighter.

Why is my Low Tire Pressure Warning Light Still on After Filling Tires?

If your TPMS light remains on after filling your tires, check that you have inflated your tires to the recommended pressure specified in the owner’s manual or on the sticker located inside the driver’s side door jamb.

Also, make sure that you haven’t overinflate or underinflated the tires, as this can trigger the TPMS light, too.

Additionally, a faulty TPMS sensor could be the cause. Each tire has a sensor that measures tire pressure, and if one or more sensors are malfunctioning or damaged, the TPMS light may stay on.

If this is the case, it may be necessary to have the affected sensor replaced. Also, something to be aware of is that some vehicles require a sensor relearning process after inflating the tires. Consult your vehicle’s manual for instructions on that.

If the TPMS light persists, try driving the vehicle for a short distance at moderate speeds, as this may trigger a system reset.

And if none of these solutions work, it is advisable to have your vehicle inspected by a qualified mechanic or dealership. There may be an electrical or system issue with the TPMS.

Can I Still Drive With Low Tire Pressure Light on?

Driving with underinflated tires is not recommended. Because it poses significant risks and can lead to inconsistent handling, diminished fuel efficiency, and accelerated tire wear.

Can You Drive With a Faulty TPMS Sensor?

As long as the tires maintain normal air pressure, the vehicle remains safe to drive. However, without the TPMS system functioning, there won’t be any alerts for low tire pressure in case one of the tires begins to deflate.

Can I Replace Just One TPMS Sensor?

Yes, it is possible to replace just one TPMS sensor. If one of the sensors malfunctions or is damaged, it can be replaced individually without affecting the other sensors.

Final Thoughts: Low Tire Pressure Light

Fact is, a low tire pressure light can be caused by various issues. Smaller ones such as natural temperature drops or air leaks, and major things like hitting curbs or running over nails.

After identifying the source of the problem, it’s important to take action and inflate the tires to the manufacturer’s recommended pressure level.

This ensures your vehicle runs smoothly and decreases any chances of an accident due to a tire blowout. Taking the time to look after your car’s tires is an investment for both its longevity and yours.

Remember to always keep an eye on that warning light and check the tire pressure on a regular basis as the performance of your vehicle largely depends on this factor.