As part of the reset sequence the game over relay should trip , which in turn will energise the reset relay .

Drop targets not resetting during startup is indicative of the reset relay not energising , possibly because the game over relay is not tripping . I have had problem with latch/trip on my Williams EM's before, sometimes needed a slight adjustment .


When the game over relay is latched you should have 'Game Over' lit on the BG and no power to most of the playfield coils , I think.

 

Yep, the game over relay now latches every time I turn the machine on and Game Over is lit on the backglass.