Mercedes-Benz R320 Tire Pressure Warning Light Stays On

Common Causes for the Tire Pressure Warning Light in Your Mercedes-Benz R320 and How to Resolve Them

Find Repair Location
Reviewed by
Bo Fader
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 Mercedes-Benz R320 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 Mercedes-Benz R320 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 of a TPMS control module failure are failing to alert the driver of underinflation or overinflation of one or more tires, failure to communicate with the body control module or TPMS sensors, or erroneously reporting incorrect tire pressure.

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.

Troubleshooting Tire Pressure Warning Light in a Mercedes-Benz R320

When dealing with the tire pressure warning light in your Mercedes-Benz R320, begin by ensuring that all tires are inflated to the manufacturer’s recommended pressure levels. This is a straightforward step that can often resolve the issue immediately. If the light remains illuminated, inspect the tire pressure monitoring system (TPMS) sensors and wiring for any visible damage or disconnections, as these can frequently trigger false warnings. Should the sensors appear intact, proceed to reset the TPMS through your vehicle's settings menu, where you can find the reset option. This process typically involves navigating to the appropriate section in your dashboard settings. If, after these steps, the warning light continues to persist, it may indicate a more complex issue that requires professional diagnostics. By following this methodical approach, you can effectively troubleshoot the tire pressure warning light and ensure your vehicle remains safe and roadworthy.

What to Do When the Tire Pressure Warning Light Stays On in a Mercedes-Benz R320?

When the tire pressure warning light stays on in your Mercedes-Benz R320, it can signal a variety of common problems that need to be addressed. The most prevalent issue is often low tire pressure, which can result from temperature fluctuations or slow leaks. Regularly checking the pressure in all tires, including the spare, is essential to ensure they meet the manufacturer's recommended levels. If the tire pressure is adequate but the warning light remains illuminated, it may indicate a malfunction within the Tire Pressure Monitoring System (TPMS), potentially due to faulty sensors or wiring. Additionally, physical damage to the tires, such as punctures or sidewall issues, can also trigger the warning light. After adjusting tire pressures, the TPMS may require a reset, which can typically be done through the vehicle's settings or a specific reset button. If you have checked these common issues and the warning light persists, seeking assistance from a professional mechanic is advisable to diagnose any underlying problems that could compromise your vehicle's safety and performance.

Why is the Tire Pressure Warning Light Staying On in a Mercedes-Benz R320?

When the Tire Pressure Warning Light remains illuminated in your Mercedes-Benz R320, it is crucial to address the issue without delay. Ignoring this warning can lead to serious safety risks, such as reduced traction, increased tire wear, and even tire blowouts, which can compromise your control over the vehicle. Additionally, driving with incorrect tire pressure can negatively impact fuel efficiency and overall vehicle performance, leading to more significant repair costs down the line. It is essential to regularly check your tire pressure, inspect for any visible damage, and ensure that the tire pressure monitoring system (TPMS) is functioning correctly. If the light persists after correcting the tire pressure, a reset of the TPMS may be necessary. By taking these steps promptly, you can maintain safe driving conditions and prolong the life of your tires, ultimately enhancing your driving experience.

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.