If you’re a Mercedes owner experiencing issues with your Eco Start Stop system not working, you’re not alone. However, when the system malfunctions, it is concerning and frustrating. You may be wondering why Mercedes Eco start stop not working: causes and how to fix.
Mercedes Eco Start Stop is a system that automatically turns off the engine when the car is idling, such as when stopped at a traffic light or in a traffic jam, to conserve fuel and reduce emissions. A Weak or failing battery causes it. Maintain and replace the battery as needed to fix this.
In this article, we will explore the common causes of Eco Start Stop system malfunction and provide solutions to fix the issue. By the end of this article, you will better understand the system and how to address any issues that may arise.
How Does The Mercedes Eco Start Stop System Work?
The Mercedes Eco Start-Stop system works by automatically turning off the engine when the car is idling, such as when stopped at a traffic light or in a traffic jam.

When the driver releases the brake pedal, the engine automatically restarts, allowing the car to resume driving. The system uses sensors, including the brake pedal switch and the battery sensor, to determine when to turn off and restart the engine.
This helps to conserve fuel and reduce emissions, making the car more environmentally friendly and fuel-efficient.
What Are The Causes Of Eco Start Stop System Malfunction In Mercedes?
If you own a Mercedes equipped with an Eco Start Stop system, you have experienced issues with the system malfunctioning at some point. Several factors cause the system to malfunction, affecting fuel efficiency and emissions. In this part, we will explore the common causes of Eco Start Stop system malfunction in a Mercedes:

Battery Issues
The system relies on the battery to restart the engine after it shuts down. If the battery is weak or unable to maintain sufficient voltage, the system won’t function properly, and the engine will not restart promptly or at all.
Sensor And Electrical Problems
Sensor and electrical problems also cause the Eco Start Stop system to malfunction in a Mercedes. Several sensors and electrical components, such as the battery sensor and the brake pedal switch, detect when the engine should be turned off and restarted. The system cannot work if any of these components fail or malfunction.
Engine Coolant Temperature
The engine’s temperature determines when to turn off and restart the engine on Mercedes. Too high or too low engine coolant temperature make the system not function properly.
Malfunctioning Brake Pedal Switch
Brake pedal switch detects when the driver releases the brake pedal, indicating that it’s time to restart the engine. If the switch is faulty or not working correctly, the system stops restarting the engine, even when the driver releases the brake pedal.
How To Fix Mercedes Eco Start Stop Not Working
You’ve been experiencing issues with your Mercedes Eco Start Stop system not working correctly. There are several steps you can take to fix the problem. Here are some of the most common solutions to Eco Start Stop system malfunctions in a Mercedes:
- Check The Battery: A weak or failing battery causes the system to malfunction. Ensure that the battery is in good condition and fully charged.
- Replace Faulty Sensors Or Electrical Components: If any sensors or electrical components the system relies on are faulty, replace them as soon as possible.
- Inspect The Brake Pedal Switch: Inspect the brake pedal switch, and if you find it’s malfunctioning, replace the brake pedal to solve the problem.
- Check The Engine Coolant Temperature: Ensure that the engine coolant is at the proper temperature and that the thermostat and engine coolant temperature sensor are working correctly.
- Reset The System: Try resetting the Eco Start Stop system to see if that resolves the issue. To do this, turn off the engine and wait a few seconds before restarting it.
- Consult With A Professional: If none of these solutions work, consult a professional mechanic with experience with Mercedes vehicles. They can diagnose and repair the issue, ensuring your Eco Start Stop system works correctly.
How Can The Mercedes Eco Start Stop System Benefit You?
The Mercedes Eco Start Stop system is a revolutionary feature that offers several benefits to drivers, making it one of the most sought-after features in modern vehicles. Below are some benefits of the Mercedes eco start stop system:
- Fuel Efficiency: The system automatically turns off the engine when the vehicle comes to a complete stop, reducing fuel consumption and emissions.
- Environmental Friendliness: By reducing fuel consumption and emissions, the Mercedes Eco Start Stop system is more environmentally friendly than traditional engines.
- Extended Engine Life: The system reduces the time the engine spends idling, which extends its life.
- Comfort And Convenience: This system provides a smooth and seamless driving experience, as the engine turns back on immediately when the driver releases the brake pedal.
- Cost Savings: Fuel efficiency leads to cost savings over time, as the vehicle consumes less fuel and requires fewer trips to the gas station.
How To Prevent Eco Start Stop System Malfunctions In Mercedes?
Preventing Eco Start Stop system malfunction in your Mercedes is crucial to maintain fuel efficiency and reducing emissions. Here are some tips to help prevent the system from malfunctioning:

- Regular Maintenance: Regularly maintain your vehicle, including the Eco Start Stop system, to ensure it functions correctly. This includes replacing faulty sensors, electrical components, and other parts as needed.
- Keep The Battery In Good Condition: A weak or failing battery causes the system to malfunction. Regularly check the battery’s condition and replace it if necessary.
- Keep The Engine Coolant At The Proper Temperature: Ensure that the engine coolant is at the proper temperature and that the thermostat and engine coolant temperature sensor are working correctly.
- Drive In The Right Conditions: The system is designed to work best in stop-and-go traffic. Avoid driving in heavy traffic or on the highway for extended periods, as this makes the system malfunction.
- Allow The Engine To Warm Up: Allow the engine to warm up for a few minutes before turning on the Eco Start Stop system. It will help the system function correctly.
- Avoid Using The Eco Start Stop System In Extreme Temperatures: It does not function correctly in extremely hot or cold temperatures, so avoid using it during these conditions.
Can You Drive A Mercedes If The Eco Start Stop System Is Not Working?
You can drive your Mercedes even if the Eco Start Stop system is not working. The system is designed to shut off the engine when the vehicle is at a complete stop, and it restarts when you release the brake pedal. If the system is not working correctly, your Mercedes will still run and drive normally, but the engine will not turn off automatically when you come to a stop. However, it’s still essential to have the system repaired as soon as possible to maintain fuel efficiency and reduce emissions.
Final Words
The Eco Start Stop system is an excellent feature that helps Mercedes drivers save fuel and reduce emissions. However, like any other system, it can malfunction due to various factors.
If you experience any issues with the Eco Start Stop system in your Mercedes, follow the troubleshooting steps outlined in this article, and consult a professional if necessary.
We hope after reading this article, you now know all about Mercedes Eco Start Stop Not Working: Causes and How to Fix. By taking care of your vehicle and keeping the Eco Start Stop system in good condition, you can help prevent malfunctions and ensure that your Mercedes runs smoothly for years.