Great game.
I’m assuming that you have checked both optos on the habit trail... as far as I can recall that’s the queue, provided the feature is lit, for that plunger to fire.
Those are switches SW80 and SW90 which are, if I’m deciphering my manual right, routed to the opto boards (back left? Back right?).
With the Gottlieb switch matrix, a failure in the X or Y grid previous to the issue can make no sense. For instance, I had a drop target switch issue which was causing issues with the spinner. A break in the strobe/return chain will influence switches (and lamps) down the line.
I forget why there are two optos on the ramp, but they are separate switches and quite easy to reverse..
34949042-619E-4CD2-9D8E-767850BF8CB0 (resized).jpeg3C9A1E29-BB1A-4BCF-B3F7-4C48FAE4FB03 (resized).jpegED542936-60E5-4BB7-AD0E-82735848AD4E (resized).jpeg