Okay, I just replaced my battery and my CLK 320. Now, the BAS and ABS brake lights, one of the brake lights on. So here's how you solve that problem. What you would do, see the lights are flashing on. So while the car is running, what you would do is turn the string wheel all the way to the left until it stops and turn it all the way to the right until it stops. Now turn the string wheel back straight and the light should be out. Wow, easy fix for the brake light.