The TPMS low tire pressure indicator is a yellow symbol that illuminates on the dashboard instrument panel in the shape of a tire cross-section with an exclamation point.
foxwell contains other products and information you need, so please check it out.
EXAMPLE OF A TPMS WARNING LIGHT
Air pressure enables a tire to support the load, so proper inflation is critical. Tires can lose one psi (pound per square inch) per month under normal conditions. Additionally, tires can lose one psi for every 10°F temperature drop. Underinflated tires and overloaded vehicles are the leading cause of tire failure. Furthermore, underinflated tires are subjected to heat and stresses that can lead to tire damage and/or unexpected rapid loss of pressure.
A tire-pressure monitoring system (TPMS) is an electronic system designed to monitor the air pressure inside of a tire and then report real-time tire pressure information to the driver. Even though a TPMS can deliver accurate alerts when properly maintained, it’s not a replacement for manual air pressure checks. Toyo Tires recommends checking tire pressure, including the spare, at least once a month and before every long road trip.
TPMS is required equipment on model year and newer passenger cars, light trucks and vans with a gross vehicle weight rating (GVWR) of 10,000 pounds or less. Some vehicles manufactured prior to are also equipped with TPMS so check your owner’s manual if you are unsure whether your vehicle has this feature.
Prior to working on your vehicle, your tire dealer should check if it is equipped with TPMS. If your vehicle is equipped with a direct system with wheel mounted sensors, your tire dealer may inform you that additional expense may be incurred if a sensor needs to be replaced and/or reprogrammed prior to beginning work on the vehicle. You should also be aware whether your vehicle is equipped with TPMS so you understand the repairs that may be required.
The yellow TPMS warning light alerts the driver that one or more tires is significantly underinflated and possibly creating an unsafe condition.
Slow down and pull over as soon as it is safe to do so and check and adjust, if necessary, the air pressure in your tires. The warning light may turn off after the inflation pressures are adjusted. However you may need to drive the vehicle for a short period of time so the system can update itself before the light turns off. If your warning light is still on after adjusting the tire inflation pressure according to your vehicle’s tire placard, there may be a malfunction with the TPMS. Bring your vehicle to a professional to diagnose the system.
EXAMPLE OF A VEHICLE TIRE PLACARD
Yes. The light came on because the TPMS identified either a system malfunction or one or more tires with pressure below the threshold. Any time the light illuminates, you should check the air pressure of your tires with a gauge.
Maintaining your TPMS may come as an unexpected expense when taking your vehicle in for service or tire replacement. Just like any part on your vehicle, the TPMS sensor can corrode or wear out over time. Your tire dealer should diagnose any problems before working on your vehicle so you understand the service required and associated costs. Tire dealers cannot bypass the TPMS system. They must repair, replace or recalibrate failed sensors and ensure the TPMS system is operational to be in compliance with the law.
When it comes to driving safety, tire pressure is always one of the hottest topics. Why does tire pressure matter? What the heck is that little annoying symbol on my dashboard? Should I under-inflate my tire during the winter? How often should I check my tire pressure?
We got tons of questions like this from our community, so for today, let's dive deep into the world of tire pressure, put our geeky glasses on and figure out everything you need to know about your tires.
The recommended tire pressure varies based on the vehicle makes determined by the manufacturer after thousands of tests and calculations. For most vehicles, you can find the ideal tire pressure on the sticker/card inside the driver’s door for newer cars. If there’s no sticker, you can usually find the info in the owner’s manual. Normal tire pressure is usually between 32~40 psi(pounds per square inch) when they are cold. So make sure you check your tire pressure after a long stay and usually, you can do it in the early morning.
After knowing the proper tire pressure of your vehicle recommended by the manufacturer, you should check your tire pressure regularly to make sure that you are in good shape.
You can check your tire pressure in auto part stores, the mechanics, gas stations, and at home. To check tire pressure at home, you need:
As tire pressure changes with the temperature a lot, and recommended tire pressures are cold inflation pressure, you should start with cold tires if possible. We mostly check the tire pressure after one night's rest to avoid the heat from the friction of the last drive, and before the temperature goes up.
Unscrew the valve cap and press the tire gauge onto the valve stem hard enough until the hissing sound disappears. There should be a reading as long as the gauge is well connected to the tire.
You can then note down the tire pressure of each tire, and compare them with the ideal psi you read from inside your driver’s door or in the owner’s manual. Make sure you read in detail, as for some vehicles, front and rear tires have different recommended psi.
If you find a tire underinflated, use the air compressor to fill your tires. You can either buy an air compressor in the auto parts store or use one in a gas station. Remember to rest your tires for at least half an hour to make sure they’re cold and the reading is accurate. If you have to fill your tires when the tires are hot, inflate them 3~4 psi above the recommended psi, and check again with your gauge when they are cold. It’s ok to overinflate a bit when filling the tires, as you can let the air out with the gauge.
After filling the tires, use your tire pressure gauge to check the tire pressure again and make sure they are in a good range. Let the air out a bit if they are over-inflated by pressing the gauge harder on the valve stem.
Tire maintenance is essential for the overall performance of your vehicle, and we highly recommend that you check your tire pressure every time you inflate your tire, each 10°F (5.6 °C) temperature change, and every 30 days.
Be mindful that don’t wait until the TPMS(Tire Pressure Monitoring System) light come on before you check the tire pressure, as the normal TPMS may:
For more information about the tire pressure monitoring system, please check our post about TPMS: What is TPMS and Why Does it Matter?
Thus, we highly recommend that you check your tire pressure regularly, especially before a long drive or heavy load driving. Also, temperature affects the tire pressure a lot, and we will explain it in the next section.
First of all, the rule of thumb is for each 10°F (5.6 °C) decrease in temperature, the tire pressure will drop by one psi for most passenger vehicles. When it comes to commercial truck tires, which are often inflated to over 80 psi (twice as much as a passenger vehicle tires), the change of tire pressure according to temperature is doubled to 2 psi for every 10°F.
For the non-nerdy readers, just remember this rule of thumb and keep in mind that you will need to monitor your tire pressure during different seasons or a sudden temperature change. For those who want a deeper dive into how psi's are determined, here's the science behind it.
The equation we use to calculate the relationship between tire pressure and the temperature is called the Ideal Gas Law. It is a good approximation of the behavior of many gases under many conditions. (Appx1) It works well for most low-pressure gases. When applied to tire pressure calculation, the error is less than 1%.
First, we take the Ideal Gas Law equation and apply it to our circumstance:
If you are looking for more details, kindly visit tyre pressure monitoring system.
where,
P = absolute pressure
V = gas volume in the tire
n = the number of molecules of gas in the tire
R = universal gas constant
T = temperature
Since we are trying to examine the pressure change according to the temperature, let's assume two tire pressures P1 & P2 at their set temperatures T1 & T2.
Given the n and R are both constants, and the gas volume in the tire is also a constant, we can take those constants out of the equation, and suddenly we get this straightforward one:
Let's say the temperature drops from 100°F to 50°F, the tire pressure at 100°F is 35 psi, so what's the tire pressure now at 50°F?
(the metric system is getting in the way, huh?)
Absolute Pressure = tire pressure + sea level air pressure (14.7 psi). So,
Put all that into the equation,
So a 50°F drop in temperature lowers the air pressure by 4.5 psi, which is pretty much the same according to our rule of thumb.
Both overinflation and underinflation affect your tire performance a lot, and serious problems might occur. According to NHTSA(National Highway Traffic Safety Administration), driving on underinflated tires increases a driver's chance of being in a serious accident by 300%. So how will a bad tire pressure affect driving safety? We will explain in detail below.
The grip is mostly associated with the size of the contact patch between the tire and the road. An over-inflated tire radically decreases the contact patch while an under-inflated tire does the opposite.
A larger contact patch gives you more grip, and this is the exact reason why lots of racers will intentionally decrease their tire pressures to create a larger contact patch on a dry race track.
However, despite the fact that an under-inflated tire will cause more fuel consumption and improper tear and wear of the tires, for most daily commuters, it might cause an even scarier problem, which is hydroplaning.
Hydroplaning is a hazardous event when a layer of water builds between the wheels and the road surface, leading to a loss of traction that prevents the vehicle from responding to control inputs. (Appx2)
Hydroplaning occurs when the pressure of the tire pushing on the ground is equal to the water pushing back up on that tire. The size of the contact patch, given the force or the weight of the tire, is the same, directly affects the average pressure the tire's putting down on the road. The larger the contact patch (by deflating the tires), the less pressure it puts on that same area. So there's a causal relationship between your tire pressure and the possibility of a hydroplaning event.
Here's a more visual explanation of what is happening between a properly-inflated tire and an underinflated tire when driving on a wet road.
To avoid a hydroplaning event, ALWAYS inflate your tires properly. Also, check your tires' treads, which make the water flow around the tires more efficiently, and of course, driving slow is always a big plus.
The contact patch directly decides the pattern of the tire's wear and tear. You don't want your tires to wear out prematurely just because you have an over or under-inflated tire.
Imagine you are a ball rolling on the ice, there's no friction between the two surfaces, how much extra force do you need to apply to keep the ball moving? Zero (Thanks, Newton). The same applies to your fuel consumption when it comes to driving on the road. The rolling resistance between your tires and the road significantly affects fuel economy, and by now we should all know the logic behind this, lower tire pressure leads to a larger contact patch, which causes higher rolling resistance, and thus, poor fuel economy.
A Michelin study showed that your tire is accountable for at least 1/5 of your total fuel consumption and a 1-bar of pressure drop (14.5 psi) would increase your fuel consumption by 3-5%.
There are of course circumstances where you want to manipulate your tire pressure to meet specific requirements. Like the aforementioned track race, or if you are driving on sand, mud, etc. However, as a daily commuter, we strongly suggest you regularly check your tire pressure, preferably once a week and anytime you might take a long road trip, and always keep the tires properly inflated!
Tire pressure is always a hot topic regarding driving safety, and it's important to keep an eye on the tire pressure to maximize fuel efficiency and safety.
We'd like to offer you our most popular ZUS Smart Vehicle Health Monitor for FREE to better take care of your car and save $$$ on car expenses. Claim your free unit here.
Top Posts from nonda:
What is a Car Diagnostic Test & How to DIY?
What Does Check Engine Light Mean & How to Fix it?
Best OBD2 Scanner & Code Reader: Complete Buying Guide
OBD2 Codes: What You Need to Know
Appendix 1 - Ideal gas law - Wikipedia.
The company is the world’s best universal tpms sensor supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.