Brake Sensor problems of the 2002 Mercedes Benz SLK320

Suddenly, for no reason, the right front brake activated, causing the car to pull to the right. This released within a second. I stopped and restarted. This happened again at about 60 miles per hour. I had the car checked by a certified mechanic. Several sensors were replaced. The problem continued several more times. I called mercedes about the problem. They wanted me to take it to dealer and pay the dealer to check the problem. The problem got worse over time. I had to replace the battery a few months ago. Since then, I have had no more problems. This causes a great deal of concern. I do not do know if the problem is fixed and if it is, what fixed it. This is know issue to mercedes.