Hey all, got an issue with the odometer and trip counter not working. I have gone through 3 speedo/ odometer units, one of which was tested for functionality before being put in and worked. Spedometer is right on the money on all of them, but no matter which unit I put in, the odometer doesn't work. Haynes manual doesn't have anything on it. Thoughts?

1990 Dodge W150 5.2l 318 Auto

 

have you opened it up and looked for any broken plastic gears? it is pretty common on the electronic speedo's

 

Came home this evening, replaced the fuel filter and noticed the VSS was a bit loose, so I tightened it back down on the side of the transfer case and took a test drive (approx 1 mile). Odometer and trip started working but were off because it racked up 4 miles then it quit working. So I took apart all 3 speedo units, 2 of them had broken gears, the 3rd is fully intact.

 

Guess my eyes are failing me, there was one tooth broken on the small odo gear. Replaced them both with new ones and it is working just fine now.