Anyone else had this happen? When the "3x" target is down and the "D" rollover is closed ,Tilt!. Now ordinarily I'd look at the switch matrix and see what switch is in the fourth corner of the square drawn by "tilt", "3x" and "D", and check that diode, but there's nothing there!

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The tilt is like a normal tilt, sound/speech and next ball kicks out after. . I will give these switches a look, thanks!

In my diagnostic work last evening I went over the diodes on the tilt mechanism and coin door, even unplugged the coin door after starting a game and POP first thing hit on the pf awards a credit still. Now this isn't that bad a problem to have with a home use machine, it always ensures a credit is on it, but it's annoying. This machine has bigger problems which i'll turn my attention to and revisit this after it's sorted better. Thanks all for the info and clearing up the Bally matrix!

Still got a couple slam tilt switches to check, but I started a game and then unplugged the coin door completely and the problem is still present. I've tested all the diodes related to this part of the matrix and they all test good. So for now, In stumped.now another problem has popped up where all three pop bumpers fire together in play and in solenoid test but I dividually when the transistor tabs are grounded manually. I suspect header pins and connectors between mpu and driver or possibly a PIA. But that issue will get its own thread if I can't solve it... Anyway, thanks for clearing up the Bally switch matrix for me and getting me pointed right, I'll update if I fix it.

Ok, I feel a little stupid but I think I figured out what was causing the multiple pop bumper firings. I had just finished working on them and had the switches set on a hair trigger. When the first one popped it set off the others....duh.

I may have the tilt issue licked too. I just cut the cap off the tilt bob switch and it now seems to be okay. At least for the couple games I have on it.