What I heard is that Mercedes experimented with a different type of wire insulation (plastic) back then that was more environmentally friendly...would decompose easily when the car was eventually scrapped. There was a problem with the plastic getting brittle and breaking up much sooner than they anticipated. Larger Mercedes engines put out quite a bit of heat.

I would assume that 9 model years later (in the case of my car), they would be making more durable harnesses, but don't know for sure.

Bosch North America said that the bad wire harness and a known software error in the LS-SFI unit are known problems at Bosch for many '94/'95 models. Would probably have been recall issues on American cars.

To answer pcmaher, I would assume that a 1995 S600 would have a similar wire harness that a DIY could do without too much trouble. Not sure though, as I am not familiar with the 600 engine, but just a larger engine and more cylinders. My job took me 3-4 hours.