Xenon solenoid probs fixed last week thanks to Quench, now it's on to the next thing.

So here's the particulars:

Right pop bumper fires in solenoid test, but not in play. Its switch doesn't register in switch test. Brown/white "row" wire does not have continuity to A4J2-14 connector.

Right inlane switch also doesn't register in play or during switch test. Same brown/white "row" wire as above, and no continuity again to A4J2-14.

Now here's where I'm baffled: schematics have the same brown/white wire leading to the #2 drop target. I test its continuity to A4J2-14, and I get the beep, so that switch is fine. I check continuity from that drop target switch to the right pop bumper switch, and I get a beep. I check from the pop switch to the right inlane switch, and I get a beep. They're all connected, so how am I not getting continuity from the pop & inlane switch to the board??

All other switches test fine in play and in switch test, and all other solenoids fire both in play and in solenoid test. A4J2 connector has been re-crimped. Right pop bumper has a new capacitor and a new diode (a 1n4004, since I don't have any 1n4148's, but I don't think that's a problem, right?)

One other thing which may or may not be related: when I check the pop bumper switches in switch test, none of the four of them register, BUT the solenoids fire. Same thing with the two slingshots, nothing comes up in switch test but the solenoids fire. I don't know if this is normal Bally behavior so I don't know if this should happen or not.

I noticed that. There's supposed to be a tilt switch in the brown/white row along with the #2 drop, right inlane, and right pop switches. Ain't no such wire to any tilt switch, as far as I can see. anyways, first thing I did was check for loose wires, which there weren't any.

Yes, I made absolutely sure of that.

I wasn't aware that those tiny 4148 diodes were even still available until today. I figured 1n400X were just the standard replacement on switches and solenoids.

Ah, there it is. I was looking on the tilt bob panel in the cab. I check continuity between the brown/white switches themselves, tilt/pop/inlane/drop target, and they all beep. So either all four should beep when I check them to A4J2-14, or none of them should. Doesn't make sense.

I threw in a spare Alltek MPU board this morning, and now the right pop and inlane switch both work. Weird. My first thought is that is was a connector issue, but again, even with a new board, either all four of those switches should work, or none of them should. I'd love to figure out what this problem is, as the Alltek board was slated for another game.

That does make sense, but I was checking continuity from the switch lugs to the the crimped contact inside the connector, not the pins on the board. I just re-crimped this connector with new contacts a month ago. The drop target switch and tilt switch give me a beep, but the pop and inlane switches don't. Yet all four switches beep when tested to each other. should be all or nothing. I initially thought there was a pinched or detached wire, but this just doesn't make sense.

And apparently the old board was not the issue after all, as I just played a few games and the right pop and right inlane switches worked at first, then they both crapped out. Waited a couple hours, powered on and started a game, the pop and inlane both worked, then crapped out again. I checked the playfield tilt and #2 drop target switches, both on the same brown/white row, tilt didn't work but the drop switch did.

Grrrrr! Started a game, everything worked. After a few minutes of play, right pop and right inlane stop working again, and playfield tilt switch too, although #2 drop switch still works. Right pop fires fine in solenoid test. This is driving me batty.

And now something new too. One of the pop bumper lamps (I have 47's in them) gets twice as bright for 5-10 minutes, then burns out. I try a new bulb, twice, and same thing happens. Then a third new bulb, and everything's fine with that pop, but another brightens and then burns out the bulb. And it's ONLY the pop bumper lamps, no other GI lamps, or not yet at least. I check under the pf for anything that might be touching the ground braids around the pop mechs, but everything looks fine. It's like this machine has a poltergeist!

I found it!!! Knew it had to have something to do with the brown/white row, just didn't see it before; curse you, crappy eyesight. A sloppy soldering job by the factory had the upper wire on the drop target switch just floating in the hole, the only thing keeping it there was that clear tubing. Fixed it and playing all night with no switch problems. Woo-hoo!! Now I can pull the Alltek and put the Bally MPU back....might as well repin the .100's first while I have it out.

Still having the pop bumper bulb prob though, in fact the same one burned out again while playing. I still can't see anything wrong down there. Is it possible that, when I re-used the bulb socket, my soldering to reattach it to the power braid was sub-par, and somehow that's creating resistance?

One other issue to note, because why not: when I power on the pin, for a fraction of a second the rear kicker is slightly energized and sometimes kicks, sometimes doesn't. It's not the kick the machine does automatically to remove a ball that may have been left in the hole. I soldered in a new diode last night and that didn't help. I have a DE Simpsons that does something similar, the outlane ball-saver kicker briefly energizes on power up, and it's been doing that for eight years, never been able to figure that one out either.

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