What is a tire/tyre Pressure Sensor Fault and How to Fix it?
Error lights are something that appears on your instrument cluster when there’s not something right or in its place but one of the most commonly misunderstood and ignored warning light if not accompanied with a message is the tire pressure sensor light which looks like a horseshoe with a exclamation mark that a flat tire and mostly people encounter it a lot of times during their drive. The truth is, even 5 PSI less pressure in your tire can cause a blowout and that’s a pretty serious risk to take on. So, don’t ignore that pesky little yellow light and don’t take a chance.
What’s good about this error is you can fix it cost effectively even if you are not a mechanic. In this blog, we will give you a complete guide on what are TPM sensors, how to diagnose fault, how to fix the TPMS error and how much it would cost. So let’s start with explaining tire pressure sensor fault.
What is a Tire Pressure Sensor?
A tire pressure sensor is a component in small electronic device (TPMS) which constantly measures the pressure inside your car’s tire and transmits information from the wheel to the vehicle’s ECU, typically via low frequency radio waves.
Most tire pressure sensors are battery powered and attached to the tire’s valve stem. As a general rule they detect when a tire’s pressure has dropped 25% or more below the recommended pressure (This is considered a dangerously low pressure level) and will trigger a warning light or message on the dash to warn the driver for the risk.
What does Tire Pressure Monitoring System Mean?
Tire pressure and safety comes hand in hand, the purpose of Tire pressure monitoring system aka TPMS in your vehicle is to warn you when one or more tires are significantly under-inflated and possibly creating unsafe driving conditions.
This light usually occurs either due to low tire pressure or a defective tire pressure sensor. This could happen due to the faulty TPMS control unit as well as the faulty wirings may need to be reset.
How often to check air pressure?
It is recommended to check air pressure in tires at least once in a month to avoid failure of tires, otherwise the damage to the tires and its pressure sensors can cost you even more than you imagine. As the pressure becomes lower, more and more of the tire comes in contact with the road. At a certain point, a section of the tire starts to run against the road as a result can and will wear very quickly. This poses a significant safety issue for everyone in your vehicle, as driving around with a low pressure tire means a much greater risk of a tire blowout. On a less worrisome level, lower tire pressure means more surface area on the ground. This increases friction and inevitably pushes up your fuel consumption. This is another reason to check your tire pressure at least once a month.
What to do if the tire pressure light is ON?
Whenever you notice this light popping up on your dashboard, 
Though in many cases, it’s simply a warning that the tires needs a top up of air. If it’s been a while since you last did this, it might be just a case of routine maintenance and your tire pressure sensors have done its job but sometimes, a regular maintenance and frequent air top-ups can’t put the light OFF then you may need to perform a tire pressure sensor reset, which is typically the button that you press and hold.
But if this trick doesn’t work, then the reason could be a faulty tire pressure sensor and it’s not uncommon for a sensor to fail.
Why do tire pressure sensors fail?
There could be a number of reasons for the failure of a tire pressure sensor but the common of all is the age. Like every electrical battery, the batteries for these pressure sensors lasts for about 5-6 years and it’s common to fail several times during a vehicle’s lifetime. Corrosion is another common reason (usually in Toyota models) that can cause the valve stems to break or crack causing tire to go flat.
Further, how often and how far the car is driven can also cause this wear and tear.
How to fix tire pressure sensor fault?
However, there are a few ways including resetting the whole TPMS system, but it is important that you learn a bit more before you kick start.
First, you need to check that air pressure in all tires is as per standard requirement. You can find the information of right tire pressure written on a label behind the driver’s door or you can refer to the manual for this information. Using a pressure gauge, you should either pump or release air from the tires to avoid both under inflated and over inflated tire dangers.
Once the tires are filled up with the required level of air pressures, it is safe to move for fixing tire pressure monitor sensor. It is not only expensive rather quite tricky to handle and repair flawlessly. Following step by step procedure can help to make it easier for you.
- Buy the exact valve stem that your car has right now.
- Locate the TPMS in the rim by separating the tire from the rim.
- Remove all nuts from the stem and push the old stem downwards with your right hand. Keep holding the TPM sensor in your left hand.
- Take the newly bought valve stem and push it upright on the place of the old one.
- Now, put and tight all the nuts which came along with the replacement stem kit.
- After stem replacement, setup the TPMS sensor back to the tire now and you are all done. There is no need to reprogram the computer for the newly installed stem.
Doing this by yourself can literally save you hundreds of dollars.
How much tire pressure sensors cost?
Just like anything else, this is largely dependent on the make and model of your vehicle, as well as whether you have a direct or indirect TPMS setup. If only the pressure sensor needs to be replaced and nothing else to do then it can cost as little as $25 per tire. If you have a direct TPMS system though, you’re most likely looking at between $50 and $250 per tire.
Since it is already expensive so if you decide to do it yourself, some special TPMS tools may be required, and the service kit costs around $5-$10 per wheel or even more depending on your vehicle’s system,. So, it may be an option to go to a tire specialist for a job like this. You’ll also need to factor in any labor costs associated with the repair. Either way, it is on higher side!
How to identify faulty TPM sensor?
It is really not easy to identify which sensor is at fault, because there are typically four identical sensors in most of the cars and it’s difficult for you to distinguish the wronged one. If you are unsure about the faulty sensor then it is advisable that you take the car to the dealer and they will be able to find the faulty tire sensor after inspection with the help of other sensors. A regular maintenance check up of your tires can save you from going into any trouble.
What if my car doesn’t have TPMS?
Many older vehicles don’t have any form of tire pressure measurement. Fortunately, there are a number of aftermarket TPMS systems that can be retrofitted to older vehicles. Many of these will use your car’s 12v lighter socket to power the TPMS display, as it is much more difficult to retrofit a warning light inside the instrument cluster itself.
