speedometer not working

My son has a 1992 lumina euro with the 3.1 and 4 speed automatic trans. The speedo stopped working and also the cruise doesn't work. I replaced the VSS and still nothing on either one. Does anyone know what to check next any help would be great...

thanks

I'd try to find a pin-out chart for the ECM and see where the VSS signal comes to it, then check for the proper signal while the car is moving...if not present, have to start chasing wiring back. Before that, make sure visually that the VSS wiring didn't fall victim to a rub or burn-through somewhere under the hood...