I guess I lied and I'm back one more time.
Eric If your reply in #30 was correct you have the solution to your problem. No MPU, No Mother Boards, No Netplex, and NO changing the lower light bulb in the candle. In door optic test when the latch is down the 0 and 1 will pulse from one to the other. No pulse, adjust the optics !! If when the optics are adjusted properly there is no pulse exchange the optics with your other machine, but only exchange them one at a time. ( one at a time will tell you which one is bad )
To adjust the optics, place some tape on the cabinet and door. Using a Sharpie draw a line on the tape that is lined up with the center of the optic. Close the door and if the Sharpie lines do not line up the optics need adjusted.
OK with a good working set of door optics and with the BV and cash can removed from the machine, ( you really don't have to remove them, but in this case please do ) Now open and close the door latch three or four times. All the BV errors will clear, now install the BV and cash can and see if the error comes back.
what they are telling you about going to Netplex Config everytime you change BVs in a S 2000 is bull shit. If after changing BVs is a S 2000 if you see CRC mismatch on the VFD just open and close the main door latch a few times and the machine will adjust for the new CRC.
Tricks of the trade
OK the tricks of my trade are trying to shift a 18 speed transmission as smooth as I can and getting from point A to point B without getting a speeding ticket or a overload ticket. I'm no slot tech, three ways I've learned about slot machines, the commen sense way, the hard way and about 6 years ago I enrolled in this sort of slot tech school. Name of that school is New Life Games and up until a couple of months ago I Read every post that was on the kind of machines I own. 90 percent of those post are bull shit but every now and then you will learn something new. This one is hard to believe but in almost 6 years I only ask for help on a machine two times and got NO reply on one of them.