RIGHT

As everything else is working in your instrument cluster as you would like...........
1) Check you have 12volts to your rev. counter.
2) Check you have your cable from the alternator to rev. counter.(obviously you have)
3) Check you have a proper earth to the rev. counter.
4) With this data, your rev. counter should work properly. It only requires these three cables. Supply.Pulse.Earth. Nothing more.
You can even remove the clock and hard wire it direct just to try. When removed you can see the labelling next to each pin.
Good luck

Hope this helps
