Just bought a used weslo cadence g-40, got it home, plugged it in, a few numbers briefly went across the screen, then nothing. We have tried the reset button by the cord at the bottom of the machine. What should we do next?

Wow, have I seen this happen, and ugly often. First, let's make sure all connections and cables are snug and in place. Moving treadmills causes strange problems, sometimes due to cable lengths when units are folded let's say, cables are pulled to Max, when uprights are up or deck us down, cable lengths relax. Repost what you might find, or Google jatinah electronics for help.