Why Is My Tire Pressure Light On When My Tires Are Fine?

Why Is My Tire Pressure Light On When My Tires Are Fine?

Indicator lights on your car are there for safety, but sometimes they can be frustrating. It’s incredibly annoying to have your tire pressure light turn on when you know your tires are in good shape!

Maybe you just purchased a whole new set, or perhaps you checked the pressure yourself, and you’re sure that they are okay. Either way, you’re probably asking, why is my tire pressure light on when my tires are fine?

Before you run to your mechanic or yell at the guy who sold you your new wheels, you might want to read this article. Below, we discuss the many reasons for a tire pressure light to turn on, and none of them have to do with over or under-inflated tires.

So, if you’re sure your tires are fine but can’t get that light to turn off, read on! We have all the troubleshooting tips to help you get it back off.

Cold Weather

The pressure of any gas, including the air in your tires, is directly proportional to temperature. Rubber tires are good insulators, but in freezing temperatures, your tire pressure may drop enough to signal your Tire Pressure Management System (TPMS).

If that happens, a short drive should turn off the TPMS indicator light. As your vehicle warms, the pressure in the tires will increase until it’s back to optimal levels.

If you find a short drive doesn’t fix the problem, cold weather probably isn’t the cause. Read on to learn about other possibilities.

Recent Tire Replacement

If you recently replaced your tires, a TPMS indicator light can be frustrating. After all, you just paid for brand new tires; you know they’re not losing pressure due to a puncture or tear!

Unfortunately, it’s common to see an indicator light appear after a tire replacement. That’s because the TPMS needs to sit against the tire’s rim, which is a rather precarious position.

During a tire replacement, it’s easy to damage the TPMS sensor accidentally. Even trained and reputable technicians run into this problem. Luckily, most are more than willing to fix it for you too. If you notice your tire pressure light comes on after a tire replacement, take your vehicle back in and let the technician know.

Your Spare Tire

In some vehicles, the TPMS monitors your spare tire as well as the tires you’re driving on. So, you might be sure your tires are fine, but did you remember to check the spare?

If not, we suggest you take a look!

Air and nitrogen both permeate rubber to a small degree, so over time, every tire loses pressure. If your space has been sitting unused for a while, that’s great, but it may be the source of your tire pressure light.

Problems With Your TPMS

If you’ve gotten this far, the problem could be with your TPMS. Tire Pressure Management Systems have come a long way, but they still exhibit issues from time to time. Here’s a few of the most common:

  • Your TPMS has its own battery, which typically has about a ten-year lifespan. After that, it may weaken, which could interrupt its signal and cause your tire pressure light to turn on.
  • A defective TPMS sensor can also cause the tire pressure light to turn on. This could happen because a substance, like tire sealant, leaked in during repairs to your car.
  • Sometimes electric components within the TPMS short-circuit due to some other fault. If that happens, the TPMS won’t be able to communicate with your car’s dashboard, and your tire pressure light will turn on.

How To Reset Your TPMS

If you’re sure your tires are okay and the problem seems to be with your car’s TPMS, you can reset it. You’ll need to dig out your owner’s manual and tire pressure gauge, just in case.

To reset your TPMS:

  1. Use the owner’s manual to locate your car’s TPMS reset button, usually in the inner console or inside your glovebox.
  2. Turn your key to the on position, but don’t start the engine.
  3. Press and hold the reset button for at least 3 seconds. You should hear an audible beep that indicates the system has reset.
  4. Start the car’s engine and drive over 20 mph for at least thirty minutes, but up to an hour, to finish the reset process.

If you see the warning light come on again, it’s imperative that you take your car in. Your TPMS sensors may need to be replaced or repaired.

Remember, your car’s TPMS is there for your safety. Continually resetting it to avoid the problem only leads to further issues down the line.

If you can’t take your car in right away, it’s a good idea to get in the habit of checking your tire pressure manually just in case. Keep a tire gauge in the glove department and do a visual check before you get in the car. If you notice a tire looks a little low, pull out the gauge and ensure it’s within a safe range.

TPMS Maintenance Tips

There are some things you can do to avoid problems with your TPMS. Here’s what we suggest:

  • Always have your car serviced by a reputable mechanic. They’ll know how to mount and dismount tires without damaging the TPMS. And, if damage does occur, they’ll be able to fix it readily.
  • Replace worn or balding tires immediately.
  • If you’re thinking about replacing your car’s tires with aftermarket wheels, be sure to check your owner’s manual first. Or, consider giving the dealership a call. Sometimes aftermarket wheels, beautiful as they may be, can upset TPMS readings.

Final Thoughts

If a tire pressure light is on, but your tires are fine, there are several things you can try. It could be the weather, in which case, you simply need to take your car for a drive. It could also be a flaw with your car’s TPMS system. A quick reset might solve things.

Otherwise, you’ll probably need to get your mechanic involved. It doesn’t mean the repair will be expensive or that it will take longer. But tire pressure lights are there for your safety, as annoying as they may be. Keep that in mind and try not to ignore them, even when they’re frustrating.

Brett Gordon

The engine behind editing at DigMyRide and the brains behind its build. During the day, Brett is a thirty-something dude from SoCal climbing the corporate ladder, but by night, he spends his time contributing to the online world of automotive tech & trends.