Looking for help and/or possibly a wiring diagram or schematic for a hitachi ex-120-3? Had it tore apart for another repair and now the thumb will not open or close. Both open and closed buttons on the joystick have continuity when pressed, but doesn’t seem to have power to the circuit. I can apply pwr/gnd at the switching valve and move in or out fine. Someone has previously patched the wiring so I’m not sure what I’m missing. Fuses all test good…
Those machines did not come from the factory with a thumb so the thumb switch wiring was done by the thumb installer. Power could come from most any place, you should be able to follow the wires down from the joystick. There were usually a couple of extra wires behind the right joystick and the seat, you might have to take the cover behind the seat, over the controllers off. Look for a wire with a female bullet type connector that has a different type of wire plugged into it. I've also seen them use the power from the aux. power outlet.
I got it. Looks like I connected the power and ground wires bullets together. Thanks for the help!