Instrument Panel Problem

I have a 2000 Buick LeSabre…the odometer gage works, but often dissolves into chinese or garbled readouts…then it comes back. I can live with it…but I have heard that it can be something simple like a ground wire somewhere…Dealer is talking big money…no dealer solution suggestions?

Yes its true that all circuits need a ground path but there really are problems in circuits with perfectly good ground paths, what I am getting at is the “check the grounds” gets used all to much.