Reseat the opto connector a couple times. Should go to a small board below the playfield in that area.

Stern uses the same opto both sides, and they glow red. If one is dim it is possible the opto is flaky.

LTG : )™

Mine had issues because the stacked Plastics next to ramp was touching it ever so slightly. I trimmed the plastic a bit and had no further issues. So you may want to check to see if the stacked plastic mound is touching left opto on left ramp at all.

I had a helluva time with this one, stern sent me the small opto board as it failed, when then new one installed it was misaligned on the ramp ever so slightly to have the light hit the ramp hole and splinter the light, hence continually triggering the opto and making the game unplayable.. a real pain in the ass, but I eventually got it figured out, also oddly had a cracked solder joint on the opto board, Im guessing the issues were independant of each other but took forever to get right..

Pull the small board the optos plug onto. Reflow the solder on the pins the optos plug onto and the big connector plugs onto.

Then put it back in and try it.

LTG : )™