hi, i own a 1992 mercedes 300se and my speedometer and mpg gauge suddenly and together began to first act irratic prior to not functioning at all. incidentally,the vehicle has 190,000 miles.
Also while driving one day they both came on for a short period of time, worked fine for about 5 miles and both once again ceased to operate. at times they both seem to slightly dance to the bumps in the road.
could someone tell what this problem could possibly be or where i might begin to look. thank u

Yeah got the same problem here on my 83SD. My speedometer doesnt work at all. but my rpm meter works when it wants to sometimes it wont work but dance around to the bumpy road but not actually work wats going on? it was like this when i bought the car!?!?