UV1700 issues, help please

[Nepa Coin Op]

I have one I sold a whiole back, garfield, out of the blue, customer tells me it comes up with error , "hopper empty" it can not be cleared off, The hopper was already jumpered when I got the game, When I set it up I set the hopper limit at 0, so it is hand pay on all cashouts, This error just popped up randomly and will not go away, I had hom power it down and reseat the jumper connections on the hopper plug and restart and try clearing it, open close door, cycle JP key ect, he said it goes away but comes right back.....anyone know of anything to try other than possibly having to clear it and reconfigure again ?


Thanks