5 Most Common Reasons Why Your Check Engine Light Came On

May 14th, 2019 by

Check engine light came on on dashboard cluster

It’s your car’s worst nightmare. The “check engine” light has appeared on the dash of your new or pre-owned Mercedes-Benz. Don’t panic. Here are five possible reasons the check engine light came on, as well as a few tips for resetting the service light in your work van or everyday car:

1. Gas Cap

While your gas cap might not seem like the most important piece of equipment in your Mercedes-Benz, it actually carries a pretty important role. It maintains pressure in the engine and prevents fuel vapors from leaking out. In some cases, the check engine light will come on when the gas cap is not tightly replaced.  We suggest that you unscrew the gas cap and re-tighten until it clicks, then allow the check engine light up to a day to reset. A loose, broken, or missing gas cap can cause your vehicle to start jerking and lower its efficiency. If the light remains on after a day, contact the service center at Fletcher Jones Motorcars of Fremont.

2. Oxygen Sensor

The oxygen sensor in your Mercedes-Benz monitors the percentage of unburned oxygen in the exhaust. Over time the sensor can get covered in ash, thereby reducing its effectiveness and leading to a decrease in gas mileage and an increase in emissions.

3. Catalytic Converter

Your catalytic converter reduces exhaust gases by converting carbon monoxide and other harmful materials into harmless ones. Most failures are down to faults with other items, but a damaged catalytic converter can mean your car will fail its emissions test.

4. Mass Airflow Sensor

The mass airflow sensor allows your car’s computer to know how much fuel is needed based on the amount of air coming into the engine. Faults can decrease efficiency, increase emissions, and cause your car to stall.

5. Spark Plugs and Wires

Spark plugs and wires are responsible for creating the original spark that initiates combustion within your Mercedes-Benz, but they can fail over time. If yours are faulty, misfires will occur.

Schedule a Mercedes-Benz Check Engine Light Diagnosis at Fletcher Jones Motorcars of Fremont!

If your Mercedes-Benz check engine light came on, it’s not something you should ignore! While these reasons might not sound too serious, they can develop into a much more complex issue over time. If you’re near San Jose, Newark, or neighboring areas, stop by Fletcher Jones Motorcars of Fremont today to have a Mercedes-Benz Master-Certified Technician inspect your vehicle. Schedule your next service visit online, or contact us to learn more about our service specials!

Posted in FAQ, Service