Putting back together my SMB after LED-ing it out, cleaning it, repairing, etc. Had to make switch adjustments using test mode as several switches were not registering so gameplay wasn't possible. All of the sudden, mid game-with-glass-off, DMD goes out. As I reach down to turn it off out of fear, the entire machine shuts down. Won't boot up at all. EFFFFFFFFFF!!!!!! I am clearly devastated. Check the playfield fuses, all look good. Check the power supply fuses, and they look good too. CRAP. Even worse, on the power supply, I see a wedged lamp bulb that must have fallen off the machine when I was changing them. Its totally possible the 44 lamp arced or did something while in direct contact w/ the power supply.

I am totally convinced I turned my pinball machine into the world's largest paperweight. HELP!

Another piece of information: The previous owner removed the grounding prong from the three-prong plug. I'm sure turning the thing on without that was dumb, but I was just planning on testing it and replacing the plug in the next few weeks.

I have to go out and buy one. I don't own a meter.

Replaced a blown fuse in the power supply (one of the ones that twist in, not the ones in the open banks on the power supply). Replacing the fuse caused the game to boot again, minus the DMD. Played a few games w/o the DMD to see if the fuse would hold. Seemed to. Then, after powering down, the game won't power back up again. Haven't rechecked the fuse but will. Any ideas?

So there's two sets of fuses on the PS. I verified all fuses are 'good', in that they beep with the test mode on the meter. However, I am suspicious of one of the fuses; which looks like someone might have removed the material inside and placed a piece of metal in there? I know its far-fetched...

***DISREGARD THIS PARAGRAPH FOUND THE FUSES ****i checked the manual. The playfield fuses are listed but the transformer fuses aren't in there. Does anyone know where a fuse listing for this would be?

I am guessing whatever line/power for the DMD is what is blowing it, and then triggering the bigger fuse (the one blowing is a 5 AMP 250v fuse).

The display was never disconnected. There was only one wire harness to the backbox from the playfield and I made sure it was reconnected before I proceeded way before the fuses blew.

I don't know what a GAL is. I am looking behind the backglass and everything looks kosher, no burn marks or anything. Given that I was able to play without the DMD powered for a few games leads me to believe the DMD is somehow shorted or something. No idea how I did that.

Given that the DMD was working when I first turned on the machine, and only turned off durin play, could my GAL be good for DMD? Don't suppose anyone has a photo and could circle the board in question...

Nope, blinking like the other boards.

Ok. I am 90% sure that one of my display fuses is bad. I swear this morning when I went over the Power Supply fuses that they were all good except the line input ones. Now that I rechecked the display ones, it appears one of them 'may' be bad? the beep test on the multimeter shows numbers on the display but doesn't beep. I think this fuse is suspect and will replace it tomorrow.

Thank you for everyone's insight. I really appreciate it!

I am in Boston. South End.

how far north are you? I grew up in Tewksbury and still have family and friends in the Tewksbury/Lowell area.

Replaced the 3/8 AMP fuse and no dice. DMD still doesn't come back. Next steps?

Also note this is my first time using a multimeter. I do not know all the terminology so please identify symbols on the meter if you want me to check Ohms or something

Ok. I know what's happening. My display fuse (3/8 amp) is blowing the instant I turn on the pinball machine. DMD came on for half a second and then off. Not exactly sure what I can do about it. Something is shorted from the power supply to the DMD, but I do not know how to begin debugging it.

The super frustrating part is there's a fuse listing on the power supply and manual, and they're listed (F2 -> f11), but those F designations aren't listed on the power supply.

They are.

I guess I don't know where to start. I know there are wiring harnesses coming from the power supply to eventually the backbox and playfield. I do not know how to identify the power supply voltages. Do i test these voltages from the fuses while the game is on? Which wires/components on the power supply should I be testing?

I know I am being childlike but I really have no working knowledge of electrical components.

I've attached the power supply in a picture. The far left fuse is the one blowing, 3/8 amp slow blow that the manual and tag list as the display fuse. power_supply.JPG

Ok, so the first fuse slot shows a resistance of .566 on the 2k Ohms scale. All the rest barely register. so its definitely something on this slot.

Pintastic, Pin 1 on the connector you were showing is 14.23v. Pin 2 and 3 are 0. Pin 4 is ~14v. Not sure what any of that means.

Just as a reminder, game plays 100% minus the DMD being down. And the DMD comes up for just a second.

None are 5v. J1 is ~14v. The pins directly to the right of J1 are both 0v from what I see. the pin directly below J1 is also ~14v

Yes, the DMD comes up but immediately goes down. Shows briefly the firmware announcement and then fuse is blown.

Bump. I know that the DMD power lines are pulling too much current and blowing the fuse on bootup. How do I proceed? How can I measure voltages etc if the fuse keeps blowing, cutting power to the DMD?

Thanks viperrwk. How do I test the diodes to see if they're good? Test voltage, resistance? What are the expected values? 95v while on? Does the machine need to be on? If so, if the fuse keeps blowing how do I get power to these components to test?

Ok, also, based on my transformer picture, I am trying to find and triple-check these fuses. I can't find F3, which should be the second display fuse. I only see the first one, at the far left of the PS, which is labeled F4. I am looking for F3.

Found this thread. Word-for-word what is happening to me so far.
http://forums.arcade-museum.com/archive/index.php/t-235896.html

Ok, VERY Carefully I checked the A4J1 connector from the DMD to the logic board. all voltages present except for the 62v line, which is expected with the F4 fuse being blown.

Umm, I think this might be the culprit. On the display board, top right, looks kinda hairy and burnt here.

IMG_0741.JPG

Manual says its a 12v Zener diode (VR4). Why would my 62v line/fuse be blowing if my 12v diode is out? Or are they just not related?

This is a crash course in electronics for me, of course.

Close ups of the board outside the system.

Are there replacement boards available? Or anyone recommend someone who can fix it?

Also, since I didn't do any work to anything in the backbox to start this whole thing, what could have caused this? Seems stuff like this is never coincidental. I don't want to do the repair work only to blow up the board again. IMG_0742.JPG IMG_0743.JPG

Viperrwk, you are right. D3 diode on the 1N4004 array of diodes appears toast according to my DMM.

$140? Ugh. Don't suppose there's some sort of repro board like what Rotten Dog does?

I guess I can send the board out for repair. Actually, Sarah from the Pinball Wizard Arcade is 40 minutes away. I can drop the board off this week.

http://www.myarcaderepair.com/

It's back!!!! Sarah at My Arcade Repair in NH (Also owner of the Pinball Wizard Arcade) repaired the board and one of my LED circuit boards as well for $30. Took her 15 minutes, I ran it up after work today thinking I'd have to drop it off and pick it up next week. She tested the board in her own SMB that she has at the arcade. I can't say enough how great a person she is. Seriously, between the arcade and the advice/teachings, she's doing a ton to keep this hobby alive.

DSCN0168_(Large).JPG

Bad diode on the LED board.

Bad bridge rectifier component and that damaged another board component. (don't know if it was a diode or a resistor or something else. It was the element with the burn marks). So she went over all the components with the multimeter, diagnosed the damaged components, and put new ones on. I don't know much more than that. I fully admit I don't know squat (yet) about electronics. I played a game of Dr. Dude while she worked on it.

I actually made a video of it last night. The Castle still isn't back on, I'm waiting for PBResource to send me the plastic clips for those.

photo.JPG

For sure, everyone on this forum has been super helpful; thanks to everyone who's helped me through all my questions. I've learned a lot and despite the fact that I get very frustrated easily, at the end I really am excited about having this up and running. The end result is totally worth it. Already have a list of things I'd love to have done for stage 2

Definitely. I'm not really sure how to go about that. There's a flathead screw at the top of the flipper but I'm assuming its not as simple as just loosening this and manually pushing the flippers. Or is it?

Also, what do you use as a 'guide' to determine when the flippers are at the right angle?

I agree with the 'even with the edge of the lane' school, although SMB does not have complex shots that might require a precise flipper alignment. The reason I like the even with the lane approach is that it makes for no interruption of the ball as it comes down the lane onto the flipper. there's a little bump/notch currently on the top edge of the left flipper and the ball can actually rest there if it comes down the lane with a very small amount of speed.

So viperrwk, in that manual shot, what number component am I adjusting to move the flipper? #6?