Current problem: flip on power, auto plunger starts automatically if balls are in the trough (doesn't occur when balls are not in trough). One ball is kicked out and auto plunged.

If I hit start, two balls are kicked out of the trough, no auto plunge.

My buddy is begging me to keep it this way. lol!

What should I look at more specifically? Explain it to me like I'm five?

Actually, when I just drop in four balls, it auto plunges 3x and leaves one in.

Found a flaky switch, but damn, how do you get at that tiny recessed bolt?

Second rollover switch is registering 4 times each time it closes / opens, swapped switch and diode, problem persists. What's next?

Think it works! Had reseated all the connectors once, but second time is a charm, hopefully.

Well, worked for a second and then I turned it off and back on to check if the error would came back: it did. What else can I look at here? I haven't really troubleshot a trough ever :\

Thanks for the late night bump!

Checked what I could - there were zip ties on the 12-pin connector, so they might have been an issue previously. I reseated everything: still the same results. I'll go grab that dielectric grease tomorrow and work that into the connectors. Thanks for all the help so far everybody!

Applied a light Dielectric grease on the header pins, same error.
Reflowed all board connections, same error.

I let the auto-plunge run it's course and it says coil #2 error (auto-plunge), don't think it's ACTUALLY an error...

Going to poke around for a bit - have an idea? Please help me out!

Revised the title, was buying some stuff for my ToM and I figured I might as well pick up some opto boards here.

It's just curious because it didn't happen before I had shopped the game, I didn't touch the trough other than cleaning it.

Cleaned - issue still remains. Thanks for the help all

Wiggled some stuff around with switch edge test and didn't see anything. Might just wait (im)patiently for the boards to arrive.

Yup only four balls

Yup - ordered them, I'll just have to wait. Sucks to put all the time into shopping the game and then it pukes :\ Oh well. I'll post after I replace - thanks for all the feedback, folks!

Replaced boards, problem still persists w/ 2 balls kicked into play and drains don't register, auto plunge fires constantly when the game gets turned on (rawwr). Bumpage.

Checking trough switches again, closing the first/third will register once in switch test.
Second switch registers 2x when I close and open. I will replace with yet another switch, but looking for other ideas on this one.

Replaced switch (again), issue persists (surprise).

Any help would be sincerely appreciated. Don't want to call out a tech, want to learn!

I had been tracing this for a bit and got to Balrog, unplugged him and the trough switch registering 2x went away and only registers once as appropriate. Came back, looked at Pinside, looks like Balrog switch might be the problem. Will have to dig into Balrog... thanks for all the help everybody!

Checked Balrog switch lugs: he is wired appropriately. Checked Balrog connector and pressed firmly on green/white wires in the connector - seems something is finicky in there, it is working for now.

I'm sure this error will come back and I'll have to check into those connectors and wires, but it looks like this issue is isolated to Balrog.

Really appreciate everyone's help on this - hopefully it helps someone in the future.