My marker lights on my 97 E420 are stuck on..there is also a green light lit up by the headlight switch thats new. I tried putting the headlight dial in all positions ...nothing has worked..I currently have unplugged the battery to turn them off. I have seen where others have had this problem ,but no fixes..if anyone is familiar with this or have any suggestions it would be appreciated. thank you.

 

the circuit board under the back seat might nead cleaning or replacement.
I had the same problem with my 01 MB E 430, and caefully cleaned the computer
board under the back, and the lights started working with the parking switch.

 

Please disconnect the negative battery cable first before attempting to clean the computer circuit board. Use a flat screw driver to pry open the black
computer box(from the bottom of the box) under the back seat right side.