I am facing a problem with the 1L coil which locks out the balls one by one from the through to the vertical eject coil.
When the machine is switched on, the lockout coil is activated a few times. Which is not normal. As a consequence, 2 or 3 balls are ejected and launched to the playfield without reason. Also, at machine switching, it says "pinball missing" or "6 ball missing" or "4 ball missing". The thing is that the unlocking coil let the balls go to the release coil (kind of VUK) which sends ball to the shooter lane.
So I wonder if because the CPU thinks not all the balls are in the through, the timeout lockout mechanism tries to activate all coils to release them, or if the 1L coil is the primary cause and by itself releases balls unexpectedly for some reasons.
I checked Q54 which is the switch driver for the through switches column. On the DMM, I get normal diode values.
Any help is appreciated. Thank you