Spider-Man (2007) Coil/Opto Problem

2huwman

Site Supporter
Sep 6, 2015
20
16
3
Isle of Wight
I've got an issue with my newly acquired Stern SM , and am hoping someone might be able to explain what's happening and a possible fix please!

The issue is that I get points added every time some of the coils activate (all three flippers, trough kicker, auto-launch, and possibly others). Using the switch test menu, I noticed that it's the Doc Ock opto that's registering when these coils are used, so I assumed that the opto was faulty, as is apparently quite common with these machines. So I swapped the opto for another known working one, but the problem remains.

I don't think it's anything to do with vibrations when the coils activate, as I can't reproduce the effect by hitting the playfield.

Also, the error only occurs when the coin door is closed & high current activated - so if I open the door in the test menu and test the flipper buttons, the problem does not happen (i.e. the Doc Ock opto does not erroneously activate).

So does this all mean it's something to do with the wiring? The only thing I'm going to try that I haven't already, is reseating the connectors going into the backboard. Beyond that I'm not sure what to do!

Any ideas or suggestions much appreciated. Thanks!
 
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2huwman

Site Supporter
Sep 6, 2015
20
16
3
Isle of Wight
Just to update, I got a bit more info about this from Chris B. & Pinside, as others have had the exactly the same issue. Seems like it's one or both of the opto lenses that's the problem, rather than the opto amplifier PCB. When I adjusted the position of the opto lenses, the problem would become intermittent rather than all the time.

I've ordered some new lenses, but I noticed that they can act either as transmitters or receivers. So I simply swapped the wires that go from the lenses into the amplifier PCB, so that whichever one was acting as the emitter is now the receiver, and vice versa. This seems to have completely solved the problem. Not sure why this would work, but it has done. At least for now!