2018 Lexus RX450hL Tire Pressure Warning Light Stays On

Resolve Tire Pressure Warning Light in 2018 Lexus RX450hL: Causes and Solutions

Find Repair Location
Reviewed by
Aisha
Written by RepairPal Car Genius
Updated January 14, 2025
0%
40% chance it's the
Tire Leaking Air
0%
30% chance it's the
Wheel Leaking Air
0%
15% chance it's the
Tire Pressure Monitoring System
0%
15% chance it's
Something else
The most common reasons a 2018 Lexus RX450hL tire pressure warning light stays on are a leaking tire, a wheel that no longer holds air, or a faulty tire pressure monitoring system.
  • Tire Leaking Air: A puncture, valve stem issue, or rim damage can cause a tire to leak air, leading to loss of pressure.
  • Wheel Leaking Air: A puncture or damage to the tire or rim can cause air to leak, resulting in a loss of tire pressure.
  • Tire Pressure Monitoring System: A malfunctioning tire pressure monitoring system can be caused by faulty sensors or a dead battery in the sensor units.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 2018 Lexus RX450hL tire pressure warning light stays on?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

When a tire pressure monitoring sensor fails, the tire pressure monitoring system control module will recognize a loss in communication and turn on the warning lamp which indicates the failure. This is most often the case. However, the tire pressure monitoring sensor may also fail by reporting incorrect tire pressures. This could cause a flat tire to go unrecognized, or a properly inflated tire to signal a low or high tire pressure warning.

When a relearn is needed, for any reason, the TPMS warning light will illuminate, and many vehicles will display a message relating to the TPMS system being inoperative or loosing communication. It is important to keep a watchful eye on tire pressures when this system is having issues because there is no warning available for underinflation or overinflation of the tires.

Wheels offer very few symptoms, but these symptoms should never be ignored. Visible cracks on the wheels may appear, especially after hitting a large bump, Most often, this will also be accompanied by loss of air from the tire on that wheel. Also, vibration in the steering wheel is very common when the tire is out of balance, and improper wheel nuts or bolts can cause creaking and popping noises to develop. Again, there are very few symptoms, but they should not be ignored.

The only symptoms requiring diagnosis for the tire pressure monitoring system warning lamp is if the warning lamp has illuminated while the tires have correct air pressure, or if the air pressure for the tires is out of specification and the warning lamp is off. This is because the overwhelming majority of cases where the TPMS lamp illuminates is due to the change in ambient temperature.

What steps should I take to diagnose the tire pressure warning light issue in my 2018 Lexus RX450hL?

To effectively diagnose the tire pressure warning light issue in your 2018 Lexus RX450hL, begin with a thorough check of the tire pressure in all four tires using a reliable tire pressure gauge. Ensure that each tire is inflated to the recommended levels outlined in your vehicle's manual, as improper inflation is a common cause of warning lights. Next, inspect the tires for any visible damage, such as punctures, cuts, or bulges, which could indicate a more serious problem. If the tires appear to be in good condition, attempt to reset the tire pressure monitoring system, as this can often clear false alerts. Additionally, examine the valve stems for any signs of damage or leaks that might be triggering the warning light. If, after completing these steps, the warning light remains illuminated, it may be time to consult a mechanic or dealership for a comprehensive inspection of the tire pressure monitoring system. By following this diagnostic approach, you can systematically address the issue and ensure your vehicle's safety on the road.

What could cause the tire pressure warning light to remain on in a 2018 Lexus RX450hL?

When the tire pressure warning light stays on in a 2018 Lexus RX450hL, it often indicates a few common issues that can be addressed through DIY methods. The first step is to check the tire pressure in all four tires, as low pressure is the most frequent cause of the warning light. Ensuring that each tire is inflated to the recommended levels can often resolve the issue quickly. If the tire pressure is adequate, the next possibility is a faulty tire pressure sensor, which may need to be replaced if it is not functioning correctly. Additionally, the sensors might require recalibration to ensure they are accurately detecting tire pressure; while some calibration can be done at home, it may be necessary to consult a dealership or a qualified technician for this task. Electrical faults within the tire pressure monitoring system can also trigger the warning light, and diagnosing these issues may require specialized tools. Lastly, it’s important to check that the sensors are clean and free from any obstructions, as dirt or debris can interfere with their operation. By methodically checking these factors, you can effectively troubleshoot and potentially resolve the issue of the tire pressure warning light in your Lexus.

What immediate steps should be taken if the tire pressure warning light remains on in a 2018 Lexus RX450hL?

When the tire pressure warning light remains illuminated in your 2018 Lexus RX450hL, it is crucial to act promptly to ensure your safety and the longevity of your vehicle. Start by checking the tire pressure in all tires, including the spare, using a reliable tire pressure gauge. Maintaining the correct tire pressure is essential, as underinflated tires can lead to poor handling, increased tire wear, and even blowouts, which pose significant safety hazards. If you find any tires are below the recommended levels, inflate them accordingly. Additionally, inspect each tire for visible damage such as punctures or bulges, as these issues can compromise tire integrity and performance. Once you have addressed any pressure discrepancies or damage, reset the tire pressure monitoring system as outlined in your owner's manual to clear the warning light. If the light persists despite these efforts, it is imperative to seek professional assistance, as ongoing issues could indicate deeper mechanical problems that require expert diagnosis. Taking these steps not only enhances your driving safety but also helps prevent costly repairs down the line.

You’ve got options with RepairPal

Whether you need a more accurate auto repair estimate or help finding a reputable shop in your area, we’ve got you covered.