Speedo working intermittently 00' Leganza

[jl93sundance]

I can't win with this stupid car, I fix one thing and immediately something else breaks. Anyway today my speedo stopped working, It will be working then just drop to 0. It seems if I shut the car off and wait a little while, it will work for a few minutes then stop again. Anything that commonly goes bad with these? Where should I start? Thanks.

[jl93sundance]

To update my problem, today I was driving home, it worked for the usual first 15 minutes then dropped to 0, but about half way home it spiked to 140 and stayed there till I was about home. Then it dropped to what I was doing for a few seconds then to 0 again. Does anybody have any wiring diagrams or anything that would help? Thanks.

[Puddle31]

sorry, have a Lanos