1990 Chev truck K2500 4x4

I have a 1990 Chev Pickup truck with a 350. the speedometer does not work. there is no power at the plug and I have checked all the fuses. Does someone have a wiring scheme for this truck or any ideas what it could be. also the speed sensor on the transfer case has been changed.
You could email me at laforet@sympatico.ca with any help.:crying:

Did the problem happen before or after the speed sensor was replaced?

No power at which plug?

//2000CAYukon

I've found on older trucks that some people grab the wires and pull hard to disconnect them. Check all wiring plugs as you trace your wiring problem.

Could it be the VSS buffer?