- Inside the cabin of your Mercedes C-Class sedan, find the instrument cluster.
- Look to the left of the instrument cluster. You will see a cluster of buttons and icons at the bottom.
- Look for the button that has the fog light symbol. The symbol will resemble two circular lights outlined in a larger circle.
- Press the fog light button to turn on the front fog lights.
- The fog light indicator light on the instrument cluster will illuminate when the fog lights are turned on.
- To turn off the fog lights, simply press the fog light button again.
