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Message: <blockquote data-quote="spalmer" data-source="post: 91014" data-attributes="member: 940">O.K. I now know what your problem is, now to find the cause. First let me explain.  When Williams went to the system 11 boards, the machines use so many solenoids, they had to find a creative way to run them an.  That machine has what they call a "relay Snubber Circuit board".  What this does is allows one transistor in the CPU board to run 2 solenoids.  On later system 11c machines it is called an A/C relay.  If you look at hte manual to that machine, you will see that there are 2 of each 1-8 listed on the solenoid list. 01a Outhole01c Knocker02a Ball through feeder02C playfield flashers03a eject hole03c insert box flashers04a 3 bank top target04c right left flashers05a raise rampect.ect.ect If you will notice, everything that you say does not work is listed with an "a".  These solenoids will only work if the relay on the snubber board is engaged.  I suspect one of two problems.  Either the Relay has gone bad or transistor Q7 on the CPU board is bad.  I am leaning toward transistor.   I am not sure how comfortable you are working on the boards but here is an easy way to find out with is bad.  Go into the solenoid test and set solenoid 01a on repeat.  You will likely get the knocker knocking repeatedly.  Take a short piece of wire and attach one end to ground.  The metal plate in the backbox should do nicely.  Next find Transistor Q7 on the cpu board.  The transistor will have a metal tab on it will a hole in it.  Touch the other end of your grounded wire to the metal tab.  If the knocker stops and the outhole solenoid fires while you have this tab grounded, the transistor is bad. Q7 is the transistor that controls the relay.  If nothing changes then the relay is bad.  I am not sure where that relay board is mounted.  Likely under the playfield.</blockquote>

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