Modern Lexus vehicles have a tire pressure monitoring system (TPMS) that alerts the driver when the pressure in one or more tires is low. If your Lexus’s tire pressure light is on, but the tires are full, there are a few potential causes.
If your Lexus tires are full, the tire pressure light could be caused by a change in temperature, new tires, a tire rotation, or simply low pressure in the spare tire. Another potential cause is a faulty TPMS sensor. These sensors can fail due to dirt, corrosion, or age.
In this blog post, I will discuss some possible causes of the Lexus Tire Pressure Light On and how to fix them
Causes of Lexus Tire Pressure Lights Being on When Tires Are Full
Here are the various reasons that can cause your Lexus tire pressure light to come on even when the tires are full:
Faulty TPMS Sensor
As mentioned earlier, a faulty TPMS sensor can cause the tire pressure light to come on even when the tires are full. Normally, physical sensors are subject to wear and tear from the elements.
Dirt, corrosion, and age can all cause sensors to fail. The sensors also use batteries with a 5-7 years lifespan. If the batteries die, the sensors will no longer work. If you think a TPMS sensor is failing, take your car to a professional for diagnosis and repair.
Outside Temperature Change
When there is a sudden drop in temperature, the air inside the tires contracts. If you live in a cold region, keep tire temperature measurements outside the house during the morning. As the temperature increases, it might lead to the tire having too much air during the day.
This is also why the tire pressure light turns on when the temperature outside drops. The tire pressure warning might activate because the colder temperature affects the measurement since air density changes with temperature.
To fix this, you need to check the pressure of your tires when they are cold and fill them up to the recommended pressure. You can find this number on the placard located on the driver’s door or in the owner’s manual.
New Tires/Tire Rotation
The TPMS in your Lexus is calibrated for the specific size and type of tire that came with the vehicle. When you get new tires, the system needs to be recalibrated.
A professional can usually do this at the tire shop. They will have the right equipment to recalibrate the system properly.
If you rotate your Lexus tires, the TPMS will also need to be recalibrated. This is because the sensors are mounted on each tire and need to be in the correct position to work properly.
Low Pressure in the Spare Tire
The spare tire usually has less air pressure than the other tires. If you have a flat tire and put the spare on, the TPMS will sense the difference in pressure and turn on the light.
This may not be a big issue because you’ll only use the spare for a short time. However, if you plan on driving long distances with the spare, you should inflate it to the recommended pressure.
Related post: AFS Light on a Lexus
How To Reset the Lexus Tire Pressure Sensor
There are several ways to reset your Lexus TPMS:
Using the Reset Button
The reset button is usually located under the steering wheel. To use it:
- Press and hold the button until the tire pressure warning light blinks three times.
- Release it and ignite the car.
- Wait for 20 minutes. The light should be gone.
Disconnecting the Battery
You’ll need to disconnect the battery if your Lexus doesn’t have a reset button. This will also clear any error codes in the system.
To do this, locate the battery’s negative terminal and remove the cable. Let the car sit for a few minutes before reconnecting the cable.
Drive The Car
Another way to reset your TPMS is to simply drive the car at or above 80 kilometers for a while. The system will automatically recalibrate itself after a certain amount of time.
Related: Meaning of BSM on a Lexus
Thoughts
The Lexus tire pressure light coming on when the tires are full can be caused by a few different things. In most cases, it’s due to temperature changes, new tires/tire rotation, or faulty TPMS sensors. You can usually fix the issue by resetting the TPMS or driving the car for a while. I hope this article has helped you understand what’s going on and how to fix it.