This is information easily found by performing a seach. Search for the words "reset light" on the W203 forum and you will find a few threads with the information you are looking for.
Anyway, here is a link to the method that worked on my 2004 C240:
How Do I Clear Service Indicator
It is quite easy to do but I had to try 2 or 3 times before I got it the first time.
Good luck
Anyway, here is a link to the method that worked on my 2004 C240:
How Do I Clear Service Indicator
It is quite easy to do but I had to try 2 or 3 times before I got it the first time.
Good luck