I had one random reset in the middle of a game the other day, and now I can replicate it 100% of the time. It *ONLY* happens when I hit both flipper buttons simulatenously. When a flipper is hit individually, there's the slightest of luminance drop on the playfield lights, but I've noticed that on plenty of other pins.

I looked under the hood and noticed that the right primary flipper coil only had 1 diode on it (between the blue/violet and blue/yellow wired lugs -- common and large winding). I was like bazinga, and went ahead and the lone diode and added two new ones. No change. Wall voltage is a generous 121VAC.

I'm going to begin the journey through the PinWiki reset section, but I was wondering if there was something my symptom points toward. I have not had nor can produce a reset any other way. I was for sure the lack of a diode would have caused it, although I suppose it should have tripped that problem earlier.

I've soldered everything on these games, and repinned more than my fair share of burnt GI connectors. I just hate having to remove a bazillion connectors to get the power driver board off.
Sigh.

$10 says as soon as I get my TAF set up it'll do the same damn thing.

I'll check the bridge rectifier, caps, and reg. too. Someone needs a cheap "kit" to swap these out so you don't have to go sourcing part #s.

http://www.kahr.us/daughterboard.html

I HATE hacks, but this looks more like a solution. I value my time and even undervaluing it at $20 an hour, this card is cheaper than the diagnostic time alone for all the possible reset causes, let alone parts.

Tough call. I'm willing to bet that aging caps and a stressed rectifier are more likely the culprit than tarnished pin headers in terms of voltage loss -- and those should be swapped regardless.

I'll report back with my findings.

I guess I should follow-up with this. Reset reproducable on double-flip on the first try every time.

AC voltage: 120
TP 2: 5.02V
BR 2 voltage test: 9.5V

Took off the board:
Tested BR1/BR2 in diode mode. All passed with .5 to .7V although you can tell both had been replaced at some point.
Tested C4 and C5 with an ESR. Both tested as new.
Reflowed solder to some questionable re-work areas, but no cracks evident.

Put the board back in stumped... no resets.

However, when I do press both flippers, the illumination dims slightly (all LED'd). I've noticed this pretty much on every game I've owned and wondered if there's a way to mitigate it?