the tech raised the cab, and the panel was right there on the left down by my foot, have to remove bout 6 or 7 bolts to access controller. and the way he talked, the 863 and 873 were very similiar. thats about all i know for now. this is my first machine.
had the same issues with my 863, bobcat tech came out, diagnosed as a bad controller box (which is located down by your left foot behind a black access panel) . he changed it out and it started right up, and ran great. NOW i cant get it to move forward or back, or bucket to raise. BUT, at least...