BSD Row 1 Ground Fault

mark adams

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Jun 21, 2015
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cambridgeshire
Looking into the above, not the Logic as with the relevant connectors disconnected, the fault disappears. The castle lock solenoid keeps operating (every 10-15 seconds) which leads me to suspect the opto on that.
Alternatively the 10 opto board, the soldering on it is a bit dodgy, the LM339's have been socketed, I replaced the IC's just in case but no change.
If i unplug the top connector on the 10 opto board and plug it back in, the fault disappears until the game is rebooted which could still be a dodgy/weak opto on the castle lock.
Is there a good source of the opto pairs anywhere in the UK?
There is a kit of circuit board and components for the 10 opto board that i found which i am considering just to eliminate it and tidy it up a bit.
Thoughts??
 

pinballmania

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Jul 21, 2011
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You cannot discount a logic fault by simply disconnecting the connectors. That’s not how it works. With the connectors disconnected you then have to short each row to each column one at a time. You should get a singular switch report in switch edge test. If all combinations of row/column report a single switch then you can discount a cpu fault. If one short causes a row short to Appear them you have a cpu fault.
 
OP
OP
mark adams

mark adams

Site Supporter
Jun 21, 2015
188
33
28
cambridgeshire
You cannot discount a logic fault by simply disconnecting the connectors. That’s not how it works. With the connectors disconnected you then have to short each row to each column one at a time. You should get a singular switch report in switch edge test. If all combinations of row/column report a single switch then you can discount a cpu fault. If one short causes a row short to Appear them you have a cpu fault.
Thats a good point, one I had overlooked, I'll give that a go tonight after I have tried cleaning the optos.
The actual fault on power up is Row 1 ground short, it then goes into game over mode and the coil fires regularly like it is trying to clear a stuck ball. It threw me after disconnecting and reconnecting the plug on the 10 opto board as it then played a completely normal game including mist multiball with no errors or misbehaviour