Hi Mike,
I have the same car. The wire harness is a known problem with this car. Has yours been replaced yet? I had a couple of weird lights (especially the check engine light) going off from bare wires touching each other. Have someone check the codes and see if it makes sense. If it doesn't make sense and you have an original wire harness, it may be time for a replacement. It's unfortunately pretty expensive (the part from MB is $740) plus the install.