Hi liftmagnet
bad - the mysterious fault is back. Good is: You can reproduce the fault. I sum up previous posts: The 10-points-chime works all the time - it never stucks, the M-100-Point-Relay and the 100-Point-Score-Drums function on all players (means they can let the ball hit the bumpers) IF, if, if the 10-Point-Score-Drum of Player-1 is not in 9th position. I show again on top of my JPG at "AAA": The schematics. IF the pin would be wired as in the schematics: Your fault cannot happen --- some kind of fault can happen (see post-5) with this wiring --- but it is not exactly the fault You describe.
So I say: Something strange has been done / has happened in the pin --- lets start unsoldering wires and do tests --- checking for continuity / Ohms / testlight lights up etc. means "do we have connection from somewhere to somewhere-else ? - or do we not have connection ?
I am not so good in using an "meter" to measure Ohms / Volts / Amperes / Continuity --- I usually use jumper-wires or testlights and/or "stripes of paper to make an switch open". I learned from many places: To get good / meaningful / true results when using an "meter": ONE SIDE of the stuff (we measure at) shall have NO WIRE(s) soldered-on --- the one point we use in our testing shall be free of anything / everything.
The "AAA" is drawn abstract --- in reality in Your pin the wires are laid / mounted maybe slightly different --- see "my green wires on the left (at "BBB")" do the same as the abstract drawing in "AAA". Also do "my blue wires on the right ...
The 10-Points-Score-Drums have TWO "End of Stroke Switches" - the moved plunger on the drum does open one switch (for to help in 10 point scoring) - the moved plunger on the drum does close one switch (on behalf of M- 100-point scoring) --- THIS switch (my "B" and "C") is good --- when it is open: No fault does show up. A very short wire (orange-mingled-with-white) runs to "my D" - the EOS-Switch that closes when the plunger moves. On the other blade of this switch ("my E") is one or more wires-color-maroon --- UNSOLDER everything. Now take Your meter and check this switch for continuity - check connection "E to D".
Next test: Do check "E to C". Next test: Do check "E to B" - do these tests twice - do them with the 9th-position-switch open and do them with 9th-position-switch-closed.
When You get the logical / we expect results: Establish an permanent Jumper "E to A" - maybe using the Jones-Plug in the Backbox instead of a looooong jumper-wire down to the chimes in the cabinet. Greetings Rolf
0Gtb-300-Work-11 (resized).jpg