Oddometer wiring/testing

[Leckypete]

My oddo has stuck at 39999, found its not too unusual but rather annoying!
Have removed the speedo and found 3 wires to it, black (ground i think)
Green (which got a resistance reading of between it and black, cant remember exactly but think was about 2k ohms)
Yellow, no reading to black or green.

I am hoping the oddo has just "stuck" and will hopefully free itself or if have to remove speedo again and open it up to move digits on to free it.

But should i have a resistance value between yellow and black as a fellow helpfull pistonheader told me the oddo has a stepper motor and although the speedo is working fine i dont know if i should have a resistance on yellow, worried the stepper motor/connection has failed?

If someone knows if the oddo is worked off same supply as speedo or seperately fed??


Thanks,
Peter.