On WCS94 I would periodically get an extra ball kicked into the shooter lane, maybe once ever 15-20 games or so. Then over the last weekend it increased it's frequency and finally puked all of the balls out at once and issued an "check uses F115, F116, and opto 12V supply" error. After checking the fuses I found that F116 had popped hard (see attached pic of blown fuse on sea of Simonis).
Further investigation found what is probably the root of the problem - blown Opto Receiver Board (see attached pic). Ball 4 was probably the culprit but it looks like ball 3 was on its way too.
My goal here is to confirm I am on the right track by replacing the Trough Opto Receiver Board (and the transmitter board since they are relatively inexpensive). I have not replaced the fuse or booted the pin since the error and want to make sure there is not another problem that caused the boards to fail. I am naturally hoping that the fuse did it's job on the mainboard and I have not suffered further damage.
Any thoughts would be greatly appreciated.