Bally Space Invaders flippers not working

Sep 17, 2017
North Yorkshire
ok guys I have been restoring my SI for a few months she's mostly up and running....
iv fitted all new transformer and rec board
and all new altek boards yes all of them lol
but I still cant seem to get the flippers to work or even the relay on the solenoid board to do anything
Screenshot_20190112-160151_Gallery.jpg Screenshot_20190112-160155_Gallery.jpg
what I have figured out so far:-
I have continuity from the flipper buttons to the lower connector on the board (blue and red wires)
and after disordering the flipper coil wires I have continuity form the upper plug (green and orange wires)
and if I connect the plugs and check continuity from the solenoid end of the green and orange wires to ground and push the little red button on the bottom of the relay in I get a good beep too!

my question is how is the relay on the solenoid driver board actuated?
I thought it was just from the flipper button inputs ?
and powered from the solenoid driver board?

thankyou for any help
this is one of the last few things I need before its running again!

cheers Oliver


Site Supporter
Jul 21, 2011
The relay cuts the path to ground from the flippers and switches. It is energised via a couple of transistors on the same board but controlled via an input from the cpu. The signal arrives on J4 pin 8 on the driver board. It also requires a power supply to be present which is 43v arriving at J3 pin 5 on the driver board.
Sep 17, 2017
North Yorkshire
OK thanks to the help of you guys I figured out its the j4 molex connector that's basically falling to bits, a light tug on one of the wires flicked the relay on for a second before pulling it out of the connector as it fell to bits on the inside :rofl:
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