bally 6000- bill validator issues and codes

[puckhead]

got a bally 6000.   WBA-13  if the bill unit is working, it works well until i remove and replace the cash can. after that i will get a code 55, 27  or a code 55, 29.  it can vary. eventually , if i pull the can and bill unit and put it back enough times, it will initialize properly.  takes way too many tries though, must more miss than hit, with  no rhyme or reason. the cash box door switch is taped closed.  those little blades that pop up and block the bill validator sensors are there, and pop up when the can is inserted.  the little plug for the back of the bill unit, are they iffy? they look lind of frail, like they might not make good contact. i also reseated the harness connectors to the backboard.

thanks

[Sunrise Side]

Power supply might be getting weak.