Williams Big Guns (Williams, 1987) Drop Targets & General Knowledge

[AlexBortone]

Hello! I have a Williams Big Guns machine. Recently, both drop target banks stopped resetting themselves. I watched a Youtube video on the problem, disassembled the boards, and cleaned the sensors with alcohol. After I reassembled both banks, I turned the game on. The drop targets still would not reset themselves. I then manually reset the targets and checked to see if the game recognized the switches; the sensors were working! But, both banks of targets continue to not reset themselves. Does anyone know of something else to check? Also, the auto fire on the far left drain is not active either. I'm beginning to wonder if the problem is in the back box. Thanks! -Alex

 

[pinballdaveh]

does the 3 coils fire on self test? does the 2 bank reset coil fire at start of a new game? the 3 coils use driver transistors Q15,Q69, and Q71. if you ground each of the tabs of these transistors one at a time does each of the coils fire. does each of the drop targets score points when they are dropped. if not does the left kicker lane and the right return lane also not score any points