interesting to read, i ve a similar problem with mine...

the mini kicker on battlefield is kicking as soon i m touching flipper buttons to go on left or right
Opto is working in test, and mini kicker activates normally when ball passes trough opto
the battlefield test is successfull and it is said mini pf is working (motor, right and left opto)
another thing mini kicker is not in optos ' beam at rest...
i swap cpu and driver boards from another working game i have and same result.
i don t know what to check now, but it seems that prob...

i saw you have a 3 lugs coil for the mini kicker, mine is only 2 lugs!

nice find...i had problems with my battlefield kicker, it was the opto board...now everythimg works good but sometimes game launch balls when i m playing battlefield, if i go to left and right too fast the game launches balls!!!

thanks as i told you before, i found issues on 10 opto boards..., i swapped another one and no more issues! i checked optos in ball trough before swapping and the reads were good but probably a vibration wake up some cold solder or something else...for now i let the new 10 opto board in the machine and enjoy it 100%