Hi!

I recent;y bought a 2001 W203 from a private party with 36k miles and all bells and whistles. The dealer maintenance records on the car are scary. About 30 different electrical problems fixed (9 bulbs, windows, instrument lights, shade motor, etc). Seems like electrical system is completely possessed. The car has 3rd party extended warranty for 2 more years, so I decided to take the risk with these annoyances.

The very first day I am having a problem with malfunction indicator regarding 3rd break light. Nice welcome to the club, ha. It comes on occasionally after car startup and the light does not work. Other times everything is fine and indicator shows no malfunction. I have also noticed that sometimes the navigation system has a slight running line. I am no experts in exlectronics, but I suspected some voltage regulation issues which mess up the electronics and could be root cause of various electrical issues.

Now, I heard about MB recall for actuator's voltage regulator. However, it only appies to cars starting with July 2001. Mine is January 2001. Do you think the same problem exists in earlier cars and they just decided to restrict the recall size arbitrarily?

Does anybody have any idea how to troubleshoot this? Can this be the voltage regulator? Will third-party voltage stabilizer device help?

Thanks for any tips!

 

Do you know the history of the car? Has it ever been flooded or partially flooded? With all those electrical issues, it would appear to be an issue with faulty grounds.