Quoted from xTheBlackKnightx:You are most likely using the old step up PCB. This is the same as the Sparky "lock and burn". Without the 20v signal the game can lock on the coil with the interlock.
Check the step up PCB and drive transistor.
There should be no diode on the coil.
I do not see a step up driver board at all for this Q24 optional coil? I took pictures of the knocker assembly and associated wires, where they go. I think I checked the Q24 drive transistor to be good, can you verify how I would check that transistor? Only other transistor I see is in the knocker assembly, 6th picture, don't know if that one is bad.IMG_1105_(resized).JPGIMG_1104_(resized).JPGIMG_1106_(resized).JPGIMG_1110_(resized).JPGIMG_1107_(resized).JPGIMG_1109_(resized).JPGIMG_1111_(resized).JPGIMG_1112_(resized).JPG
So, I do not see a step up driver board at all. How do I test the transistors correctly? If your looking at that assembly from the top (pic 1), the right wires go to the knocker coil, the middle wires go to my red & violet/grey connector in the cabinet towards the front left, and the left wires go up to the head and piggyback on that connector (pic 4). The coil ohmed continuous at the leads, connection removed, so the coil is OK. Another thing that does not make sense is the power voltage for Q24 is saying 5 VDC, is that the proper voltage to power that knocker coil? Help on where to go or troubleshoot next would be greatly appreciated!