mercedes check engine light reset without scanne

To reset the check engine light (CEL) on a Mercedes without a scanner, you can try a few different methods. However, these methods only reset the light temporarily and do not address the underlying issue that caused the light to come on. If the problem isn't resolved, the check engine light will likely return. Here are some ways to reset it:

1. Battery Disconnection Method

• Step 1: Turn off the car and open the hood.
• Step 2: Locate the negative terminal on the battery (marked with a minus sign "-").
• Step 3: Use a wrench to disconnect the negative terminal cable from the battery.
• Step 4: Leave it disconnected for about 10-15 minutes.
• Step 5: Reconnect the negative terminal, ensuring it is tightly secured.
• Step 6: Start the car and check if the check engine light has turned off.

Note: This method may reset other electrical settings in your car, like the radio, clock, and drive modes.

2. Fuse Pulling Method

• Step 1: Turn off the vehicle.
• Step 2: Locate the fuse box, usually under the dashboard or in the engine bay.
• Step 3: Find the fuse associated with the engine control module (ECM) or check engine light (you can consult your owner's manual for the specific fuse).
• Step 4: Remove the fuse for 5-10 minutes.
• Step 5: Reinstall the fuse and start the car.
• Step 6: Check if the check engine light goes off.

3. Drive Cycle Method

• Step 1: Start the car and let it idle until it reaches normal operating temperature.
• Step 2: Drive the car at a steady speed (around 50-60 mph) for 10-15 minutes, giving the car’s computer time to perform self-diagnostics.
• Step 3: If the issue that triggered the light is resolved, the light may reset automatically after this drive cycle.

4. Using the Odometer Button (Certain Models)

On some Mercedes models, you can reset the check engine light using the trip odometer button:

• Step 1: Turn the ignition to the "ON" position (without starting the engine).
• Step 2: Press and hold the odometer reset button (or the trip button) on the dashboard.
• Step 3: Hold the button for about 10-15 seconds or until the check engine light starts to blink or turns off.
• Step 4: Release the button and check if the light is off.

5. Driving for a While

If the issue that triggered the check engine light is a temporary or minor problem, sometimes simply driving the car for a few days can cause the light to reset itself.

Important Note: While these methods can reset the check engine light, they do not fix the underlying issue. If the light comes back on, it is crucial to get the car diagnosed by a professional to identify and address the problem.