Peugeot 206 Brake Light Error

Sounds annoying. The symptoms point to a bad brake light switch. Like a fuse blowing at home. Have you checked the switch for damage or loose wires? Does the error pop up when you start the car, or only when you hit the brakes?

I checked the switch and wires, but nothing obvious. The error only shows up when I press the brake pedal. Could it still be the switch, or could something else be wrong?

Right, the pedal triggers it, so it's more likely the switch since the circuit closes when you press the pedal. But it could be a wiring problem around the switch. Since you don't see anything and with that mileage, I'd suggest a quick garage visit. They can test the switch and wiring properly.

Thanks for the advice. I checked the Peugeot service info and found that this model can be sensitive to the brake pedal position, which can be fixed with a reset. I went to a workshop to get it reset, and it worked! The error is gone, and the brake lights are working. It cost 0€.