Speedometer and Odometer acting like Tach

[Green Machine]

I am trying to solve an issue with my speedometer and odometer. When I start the engine the speedometer races like the tach should and the odometer begins to count. The tach does not move. When the engine is shut off the speedometer needle stays at the last setting. When the key is turned to the ignition point then the speedometer needle resets to the bottom position. Any help is welcomed.

[stnicjr]

A few years ago my '97 Safari developed erratic tach and speedo problems. I am not able review my records from my current location. Maybe this can help you, though. I recall my mechanic checked and found my problem to be electrical and located on the front wall of the engine compartment. I can't recall if it was a failing electrical connection that he repaired or a fuse. It was a very inexpensive repair, though. I could have fixed it myself with a little more thinking on my part. All this to say you might want to check the relevant wiring coming up from your transmission and forward engine that is routed along your front engine wall. Hope this helps.
Stnicjr
1997 Safari 30
Cat 3126/ Allison trans

[Green Machine]

Thank you for the guidance. I have already repaired four wires dealing with the dash lighting. I do see some rusty connections….
Thanks again.

[05wingrider]

While you are working on the dash wiring, run a new ground for the gauges as well. I ran one from the front frame just for the gauges since they put everything in the dash on one ground point on my '96.

[Green Machine]

Thanks. I will do that. Do you know if this could be a sensor issue? Grasping at straws……

[oldcobia]

I’ve had similar issues. My tach and fuel gauge are erratic sometimes. Seems to happen more often when running generator. Stops for a moment when turn on blinkers or headlights. Feel sure it’s a ground issue just haven’t spent the time to track it down yet but it’s on the list

[TDJohn]

It almost sounds that the wires feeding the tach and speedometer were accidentally reversed/swapped. Was there any sensors changed or work done on the coach, where this could have accidentally happened?