Are you frustrated and confused because your tire pressure light keeps turning on, but your tires are properly inflated.
If you don’t know what to look for, this can drive you crazy. Don’t worry. I’m here to help.
In this post, I will go over nine common reasons that can cause a false tire pressure light. I will also let you know how you can fix it and if you should be worried.
Let’s dive in.
1. Cold Weather
If you live in an area where the temperature gets very cold, you may experience your tire light turning on when your tires are not flat. You may experience this when your first turn on your car in the morning. This is because temperatures tend to drop the lowest overnight making this more likely to happen.
Air molecules get smaller at low temperatures. The air in your tire is not leaving but instead losing volume. As a result, this can cause your tire pressure light to turn on.
Don’t worry. You typically don’t need to add air to your tires. However, when you begin to drive and your car heats up, the air molecules will expand. As a result, your tires will re-inflate, and your tire pressure light will turn off.
You can expect your tires to increase about 1 PSI every 5 minutes for the first 15-30 minutes of your drive. After the first 30 minutes, your tires’ PSI will stop changing because the tires have reached the optimal temperature.
If your tire pressure light stays on after 30 minutes of driving, you should either add more air to your tires or have your tires inspected by a professional.
You should only expect the cold to affect tire pressure by around 3-4 PSI. If your tires are more than 4 PSI below the recommended PSI levels, you should also have considered adding more air to your tires or having your tires inspected by a professional.
2. TPMS Needs Calibration
A faulty TPMS system can also cause a false tire pressure light. This happens when your TPMS system is not operating properly and requires additional calibration.
A faulty calibrated TPMS can cause a false reading that leads to your tire pressure light turning on. One way to determine if your TPMS system needs to be calibrated is if your tire pressure light is on, but your tire pressure meets the manufacturer’s standards.
You can do this by testing your tire pressure with a tire pressure gauge. Test each tire and make sure they meet the manufacturer’s standards. You can find the ideal PSI for your tires on the outside of the tire or on your owner’s manual.
You are probably wondering what causes TPMS systems to give a false reading? In some cases, the sensor that reads your tire pressure may be broken or worn out.
Otherwise, there are some maintenance or other situations that may require your TPMS to be calibrated.
Here are some standard tire maintenance or repairs that require a TPMS calibration:
- Replacing your tires
- After rebalancing your tires
- Rotating tires
- Changing the wheels
- After having a flat tire
On Modern-day vehicles recalibrating your, TPMS is not a difficult job. Using a diagnostic TMPS handheld device that connects to your OBD port is a great tool to complete your recalibrating needs.
3. The Tire Pressure Sensor Is Damaged
The tire pressure sensor is one of the most important parts of your TPMS. The sensor is the part that provides the direct reading of your tire. Unfortunately, these sensors are not built to last forever and as a result, they can break or stop working.
Tire pressure sensors often stop working due to some direct impact or normal wear and tear on the sensors. For example, driving over large potholes or over rough roads can sometimes cause a sensor to stop working.
Tire pressure sensors often stop working in offroading vehicles or vehicles that drive over rough terrain frequently. Driving on your tires with a low tire pressure can also eventually cause issues with your tire pressure sensor.
Tire pressure sensors are located inside the tire attached to the inner wheels close to your valve stems. Therefore, When your tire flexes due to hard impact or low PSI levels, your TPMS is vulnerable and could be damaged in this event.
To help prevent your TPM sensors from getting damaged, walk around your vehicle, look for damaged tires and check the PSI levels manually in each tire using a tire pressure gauge.
4. Recent Tire Change
Changing your tires can also cause a false tire pressure light to turn on. If you’ve recently changed your tires and your tire pressure light turned on recently then this can be the cause.
Often times, after changing your tire pressure its likely that you will need to reset your TPMS. Most professional mechanics will rescalibrate the TPMS after they change or rotate your tires.
This issue often happens if a professional forgets or if you change your own tires at home or due to a flat.
5. TPMS is Malfunctioning
The TPMS system has several components that can be cause a malfunction. If your inspect your sensors and they are working properly and your tires are inflated to the appropriate PSI but your tire pressure light is still on then your TPMS is likely malfunctioning.
This could be happening due to a wire short, computer issues, among other things. If this is the case, you should have your car inspected by a professional. Identifying and repairing a malfunctioning TPMS system requires experience and should be done by professionals or enthusiasts with plenty of experience.
6. Adding Too Much Air To Tires
When your tire pressure light turns on most of the time we think we have low air. But your tire pressure can also turn on if the PSI in your tires is too high.
This happens most often when people fill up their tires. They accidentally put to much air inside their tires. As a result, the tire pressure light will not turn off. It will remain on until the tire pressure in the tires is released.
Another common reason this happens is when people add air to all their tires when only one or two needed air. It’s important that you always measure the PSI of your tires before and after adding air.
It’s recommended that you stay withing the manufacturers listed range on the tires. The most common range is between 32 and 40 PSI. Even going over the maximum PSI by 5 PSI can causes issues when you are driving.
Over-inflated tires are just as dangerous or possible more dangerous than under inflated tires.
If you suspect you have too much air added to your tires. Using a tire gauge, release air out of the tire until the tire gauge reads the correct PSI level in each tire.
7. ABS Problems
ABS ( Anti-lock Brake System) helps vehicles not slide during an emergency stop situation. If you have ABS issues, this can affect your TPMS system. Some vehicles have an indirect TPMS system that relies on the ABS to calculate the tire pressure.
TPMS light that will not go out cause be an early sight of ABS issues. Before assuming this is your exact issue with your TPMS system. Refer to your owner’s manual to see if your vehicle type uses an indirect TPMS system that relies on the ABS braking system.
8. Slow Air Leak
Another common problem is that your tire has a slow air leak. This is typically caused by a puncture in your tire or wore out tires.
The leak will typically go unnoticed at first but as it gets worse it will cause the tire pressure system to trun on. Many advanced or newers tire pressure systems can detect a leak.
As a result, if your TPMS detects that your tire pressure continues to fall it will tirgger the light. If you light is staying on even after you fill up your tires with the correct PSI levels then its possible you have a leak.
Its best to inspect your tires for any punctures or turn-off your car and listed for any air exiting your tires. Another common trick used is wet your tire and look for any bubbles that might be forming on the surface of the tires.
Depending on where the air seepage is coming from, your local mechanic may be able to patch up your tire with minimum cost. In the short term, you can use a can of fix-a-flat to slow down the leak until you get the tire repaired.
9. Low Spare Tire Pressure
Suppose you notice your tire light stay on after replacing your damaged tire with the spare tire. Your spare tire may need additional air for the TPMS light to turn off.
Spare tires come equipped year TPMS inside the tire for safety. It allows the driver to monitor tire pressure even when one wheel is replaced with a spare tire. Simply adding air to the recommended factory spec should fix your TPMS light issues.