Flashing Puzzle: Why is My Tire Pressure Light Blinking?

The tires in our cars are perhaps the most important part when it comes to safety. Even the safest vehicles won't perform well with tires that are not inflated properly, worn out, or damaged. Therefore, it's crucial to take care of your tires regularly and tackle any issue with them on time. By doing that, you will ensure a safe ride, but you could also potentially save some money.

With that said, the easiest way to take care of your tires and the safety of your car is to check the pressure regularly. By doing this, you will ensure that they always perform at their best while minimizing fuel consumption and improving the driving experience.

Modern cars are equipped with a Tire Pressure Monitoring System (TPMS), which can notify you when it notices a significant pressure loss. It does that by blinking the red tire pressure light on the dashboard. As a result, most drivers react to this light and immediately check the tires, which is a good thing to do.

Nonetheless, the TPMS isn't there to notify you of a slight pressure loss and can't be used for regularly checking the tire pressure. For that reason, I wrote an article where I'd explain all the nuances of the Tire Pressure Monitoring System and why it matters. I will also tackle the tire pressure light on your dashboard and when it starts to blink.

So, let's solve the blinking puzzle = of the tire pressure light, what it means, and what you should do about it!

Introduction to Tire Pressure Monitoring System (TPMS)

The Tire Pressure Monitoring System, often referred to as TPMS, is an invaluable component of modern vehicles. Since it's directly related to road safety, it became mandatory on all new cars in the USA in 2008 and in Europe in 2012.

1. Understanding the Role of TPMS

Maintaining proper tire pressure ensures your vehicle always operates at the optimum level, i.e., as the manufacturer planned. TPMS is designed to help prevent such issues by alerting drivers of low tire pressure early on, thus allowing them to address the problem before it leads to dangerous situations or costly repairs.

However, the TPMS is designed to alert drivers when the pressure in one or more tires falls below the safe limit, which is typically 25% below the manufacturer's recommended level. For instance, if the recommended tire pressure for your vehicle is 32 psi (2.2 bar), it would need to fall below 24 psi (1.6 bar) for the tire pressure light to start blinking. As such, the TPMS can't be used as a measure against underinflation, meaning you will still need to regularly check the pressure in your tires.

I tell you this because people often overuse that "safe limit." Namely, your vehicle will still perform seemingly fine at 28 psi (32 psi recommended), but the tires will wear faster, the handling at the limit will be much less predictable, and the tires will provide less traction. Not to mention, driving at lower psi leads to accelerated and uneven wear, meaning you will need to replace the tires sooner.

The bottom line is that the tire pressure light might start blinking if you never check your tires, i.e. when things go very south. However, it could also indicate a problem with the tire, like a puncture, damaged bead, or cracks on the surface. All of these issues lead to air escaping from the tire and should be immediately acted upon.

In conclusion, I strongly recommend using the tire pressure light only for serious issues like punctures. In other words, check your tire pressure regularly and only use the tire pressure light to notify you of issues with your tires.

2. How Does TPMS Work?

Most TPMS utilize sensors inside each tire, either directly on the valve stem or attached to the wheel's interior. These sensors monitor the pressure inside the tire and transmit this information to the car's onboard computer. If the pressure in one or more tires drops below the threshold, the computer triggers the TPMS warning light on the dashboard to alert the driver.

Some premium vehicles will show the exact pressure in each tire on the dashboard. These systems are frankly amazing, as they eliminate the need to check tire pressure regularly. However, they are costlier than regular TPMS, which reserves them only for some expensive vehicles.

Decoding the Tire Pressure Warning Light

The tire pressure light looks like an exclamation mark placed within the outline of an underinflated tire. The design varies between makes and models, but it is easy enough to understand, even for novice drivers. On most modern cars, you will even get a "Check Tire Pressure" text written on the screen in the instrument table.

1. Why Does the Tire Pressure Light Come On?

The TPMS light illuminates when the system detects that the pressure on one of the tires is too low. This is the primary function of the light, but here comes a headscratcher – it could also indicate a problem with the tire pressure monitoring system itself.

I know many people that literally scratched their heads when seeing the tire pressure light illuminated, checked the tires, and saw that they were fine. But few people know that the TPMS light has two behaviors: blinking and solid illumination.

2. The Difference Between a Solid and Blinking Light

A constantly illuminated tire pressure light indicates that one of the tires is underinflated. In this case, I recommend finding a safe place to stop and check the tire pressure as soon as possible. In case of a puncture, replace the tire with the spare, or use the tire repair kit in your trunk.

Meanwhile, a blinking tire pressure light indicates that there is a fault with the TPMS system. Usually, it will be a malfunctioning sensor, which will stop communicating with the ECU. If the TPMS light blinks for about a minute and then stays solid, it's a sign that the system is not working properly and needs to be inspected.

Common Causes for a Blinking Tire Pressure Light

Although a puncture is the most probable, other factors could also cause the tire pressure light to illuminate.

1. Seasonal Changes and Tire Pressure

The pressure inside any vessel varies with temperature changes. The more heat you add to the system, the higher the pressure will get. It's the same with the tires on your vehicle, which will gain pressure if the environment is hot and lose pressure if the surrounding area is cold. Thus, it's common to see the TPMS light come on during seasonal changes, especially at the start of winter.

2. Tire Damage or Punctures

Apart from a puncture, which obviously lowers the pressure inside the tire, other factors can also cause the issue. For instance, a damaged rim or tire bead can lead to a loss of pressure and is a problem a professional technician can easily rectify. However, cracked tires, which can also lead to air loss, will probably need to be replaced with new ones.

3. TPMS Sensor Issues

Like with any electronic system in your vehicle, the sensors in the TPMS can fail over time. A malfunctioning or damaged sensor might cause the TPMS light to blink. This is often due to battery failure in the sensor, damage from road debris, or corrosion. If a sensor problem is suspected, a professional will need to diagnose and rectify the issue.

Resolving the Blinking Tire Pressure Light

Once you see the tire pressure light blinking, it's crucial to immediately stop your vehicle in a safe place and investigate. By doing this, you will ensure your vehicle's safety and optimal performance.

1. Checking and Adjusting Tire Pressure

The first thing you will need to do is very obvious – check the tire pressure with a special gauge. Use the gauge on each one of your tires, and write the values down (you can even use your smartphone).

For the most accurate reading, I recommend doing it while the tires are cold, as heat increases pressure. However, you can also measure hot tires if you are in a hurry. You will get higher values, but you will still be able to notice if one tire is way below the average.

If the pressure in one or more tires is below the manufacturer's recommended level (which is usually indicated on a label inside the driver's side door or in the vehicle owner's manual), you will need to inflate the tires to the correct level. Many gas stations offer air pumps for this purpose, but you can also use your pump (if you have one). Make sure you inflate the tires while cold (wait for 15-30 minutes) to ensure proper inflation.

After adjusting the tire pressure, the TPMS light might continue to blink. Don't worry, as TPMS sensors need a few minutes to reset. Drive your vehicle for a few miles, and the tire pressure light should be gone. That said, if the light continues to blink, it might indicate a problem with the sensor itself.

2. Seeking Professional Help: When to Visit a Mechanic

Reinflating car tires is a straightforward job that pretty much everyone can do, but replacing the TPMS sensors is definitely not. Thus, if you are sure that your tires are inflated properly, yet the tire pressure light still blinks, I strongly recommend visiting a mechanic, as he can accurately diagnose the problem and suggest the appropriate solution.

Thinking of replacing the sensor yourself? Let me tell you that it is challenging, primarily because it requires special tools to remove the tire from the rim, but also special software to let the ECU know that a new sensor has been installed.

In other words, you will need a special machine to remove the tire, a laptop with an OBDII connector, and software on your laptop (usually an original automaker program) that will let you reset the TPMS system. Not doing the job properly won't be a safety issue, but the tire pressure light will continue to blink, meaning you lost time on nothing.

With that said, if you have the proper tools at hand (like I do in my garage), you can do the job. But for most people, visiting a certified service or a special tire shop is the best bet.

The Importance of Regular Tire Maintenance

Regular tire maintenance plays a vital role in vehicle safety, performance, and longevity. It can also help prevent issues that could cause the tire pressure light to illuminate.

1. How Regular Maintenance Can Prevent TPMS Issues

Regularly checking your tire pressure is a simple and quick task, but most importantly, crucial in ensuring your vehicle's optimal performance and safety.

Keeping your tires at the correct pressure can prevent a range of issues, from uneven tire wear to poor fuel efficiency and potentially dangerous blowouts. It can also help avoid unnecessary TPMS alerts. Even so, not many people check the tire pressure regularly.

A safe practice would be to check the tire pressure at least once a month or each time the temperature outside dropped significantly. Also, to be safe, you should check the tire pressure before going on longer journeys. For convenience, use the fast inflators at the gas station at the same time you are fueling your vehicle.

But it's not just the tire pressure – you can also mitigate many issues by rotating and balancing your tires regularly while also inspecting them for damage. Regular tire inspections can help identify issues like cracked tread or sidewall early, allowing you to address them before they lead to a TPMS alert or more serious problems.

2. Long-term Effects of Neglected Tire Pressure Warnings

There is a reason why the tire pressure light is red or orange – you should not ignore it. If you just continue driving as usual, underinflated tires can lead to poor fuel efficiency, worse handling and stability, lower traction, and increased wear. Underinflated tires are also prone to blowouts, which usually happen at higher speeds and can cause serious accidents.

Oh, and knowing that one of the tire pressure sensors doesn't work shouldn't mean that you can just continue using your vehicle as usual. Yes, it will be safe to drive, but the TPMS system might not alert you, potentially leading to the same risks.

Conclusion

The tire pressure light is an ingenious solution to a problem that plagued the automotive industry for decades. Still, the system also relies on you, the driver. The light has finished its job with the illumination/blinking, and it's on you to react by re-adjust the pressure or bringing your vehicle to the shop for inspection.