Had the same problem with my 92 300se. Sent the whole cluster to George Murphy, the National Technical Dierctor for MB, who has a private business repairing electronic components for a variety of MB models. Haven't had a problem since. Think it was around $300.00 but George will quote you when he has a chance to inspect it. Turnaround was 7-10 days if I remember correctly. It's been a couple of years. Check the STAR for his contact info.

Tim