Quoted from Trooper11040:Every opto on J1 is non functional. Leaves me to believe that the opto board is the issue[quoted image]
Can you test the lm339 using this pinwiki method https://www.pinwiki.com/wiki/index.php?title=Williams_WPC#7_Opto_Board_Testing
Or zaza test process https://pinside.com/pinball/forum/topic/wpc-trough-opto-issue#post-5088875
These will verify if the lm339 is bad