I bet one of those clusters are cheap (sarcasm). Would be interesting to know just how much these things are.

This was also a common problem on the early Lexus LS400s (1990 up to about 1994 (so far). They typically last about 10-15 years before they go. There have even been some reports on this happening on the 1995-96 models, which are a newer design, but not yet on the 97-00's - basically the same. Some of them also had "needle" light problems, as well as faulty gages.

The LS400 had this "state of the art" instrument cluster since its introduction in late 1989 (USA). I remember it was one of the raves back then.
My 85' Mercedes instrument cluster looks archaic compared to my old 90' LS400s instrument panel. But not as prone to trouble though- so that is a plus.

Its about a $1000. replacement on those cars, but I think they are actually repairable on those. Not sure of the 00' Mercedes unit is repairable or not.

Good luck.