Super Mario Bros Mushroom World Drop Target Problem...

[melarky]

I picked up a Super Mario Bros. Mushroom World pinball a little while ago and have been working on it since. I think I have everything pretty well fixed on it except for one thing that has me stumped. It's sort of hard to explain, so I also shot a video of the problem and put it up on youtube and will post the link to that video below.

Basically, the rules of this pin have you advance through 8 levels, and the way you advance through the levels is by knocking down drop targets. Each level it will light up (and pop up) the drop targets for that level. When you knock one down, the light goes out too, and once all drop targets are down, the DMD tells you the name of the new level and the drop targets reset (in a new order) and you have to knock them down again to advance.

My machine works perfectly as long as you don't drain any balls, I have been able to make it through all 8 levels (it just starts you back on world 1 and cycles through them again), but if you drain a ball (no matter what level you are on), when it resets the drop targets, it lights up an extra drop target (or sometimes multiple extra drop targets depending on the level you are on when you drain the ball). The extra drop targets that get lit, don't pop up though, so there is no way to drop them and advance levels (I have even tried to rock the drop target to hit the switch, but that doesn't seem to do it either, there is no way to un-light that drop target, so you are stuck on that same level from there on out).

The video of this happening can be found at

I did just change out a transistor on the main driver board (that was for a coil that was stuck on), but everything else there seemed fine, didn't see any other problems on that board. I'm not even sure if that would be something that could be caused by a bad part on a board as it almost seems like something wrong with the programming, but I'm not even sure really where to start looking. Does anyone know what this could be or where I should start looking to track this down? Any help is really appreciated, I'm so close to getting this machine up to 100%.

[lilshawn]

i would replace the diodes...

you will probably notice..... that perhaps.... the drop targets and the switch for the ball trough, maybe some other things....maybe on the same switch matrix row or column

you may be getting a phantom switch press from the ball trough going someplace thats messing with the system and confusing the computer.

if there wasn't too many (if i remember this was a small unit) i would replace the few switch diodes, just to eliminate that for sure...

[lilshawn]

can't find a manual right now....

if you get to level 3 does the same target stay lit or does another stay lit?


edit:

also if you where to pull up the offending drop target then hit it down will it reset or stay lit?? i'm just thinking maybe the drop targets only register a hit while it's on the way down (like 1/2 way down)

[melarky]

can't find a manual right now....

if you get to level 3 does the same target stay lit or does another stay lit?


edit:

also if you where to pull up the offending drop target then hit it down will it reset or stay lit?? i'm just thinking maybe the drop targets only register a hit while it's on the way down (like 1/2 way down)

Different levels light different lights, but I think it's consistent (like the level in the video always lights that one light as the extra etc..., but I'll test that out to be sure).

I also think lifting the drop target up and then dropping won't make a difference (we tried it before and it didn't work, but we have done things to the machine since that I guess could affect it (fixing that one board) so I'll test that again too to be sure.  Thanks for all of your help suggestions, I really am at a loss as to what could be causing it so this is great.

[lilshawn]

since coughdouchebagBobFesjiandouchebagcoughcoughcough Gottlieb doesn't have LEGALLY anyplace i can get a manual...

i'm thinking that the switch is only "drop down detect"

ie: it's only detecting when it's dropped down...not when it's hit, and not when it's up. so what i'm thinking is...while all are up... zero switches are pressed......it trips the targets to drop down it's not going to need...fires the solenoids to release the 8 other targets it wont be needing....detects 8 switch closures.

i'm feeling that there is a bad diode in the switch matrix thats causing this...you might not be noticing it when the game is in play because the computer may be compensating for it.

the switch matrix diode board has only a few diodes on it, i would go ahead and replace them just to eliminate that for sure...besides whats 50 cents worth of parts??

[melarky]

since coughdouchebagBobFesjiandouchebagcoughcoughcough Gottlieb doesn't have LEGALLY anyplace i can get a manual...

i'm thinking that the switch is only "drop down detect"

ie: it's only detecting when it's dropped down...not when it's hit, and not when it's up. so what i'm thinking is...while all are up... zero switches are pressed......it trips the targets to drop down it's not going to need...fires the solenoids to release the 8 other targets it wont be needing....detects 8 switch closures.

i'm feeling that there is a bad diode in the switch matrix thats causing this...you might not be noticing it when the game is in play because the computer may be compensating for it.

the switch matrix diode board has only a few diodes on it, i would go ahead and replace them just to eliminate that for sure...besides whats 50 cents worth of parts??

Thanks lilshawn, I'll have to find out what kind of diodes to get and then get them ordered, that would be awesome if that fixes it.  There isn't like a standard diode for these is there (like all pinballs use xyz diode for the switch matrix?).  If not, I'll just grab some ones from mouser (always like to get parts from pinball and arcade vendors first if they have them to support the hobby).

[melarky]

Been so long since I've had a System3 that I can't remember if the drop targets have 'smart switches' or not.  You can replace them with regular switches, though.

Why haven't you lifted up the playfield and taken a look already?



Lilshawn, you're fooling yourself if you think anyone besides Steve Young is monitoring Gottlieb IP on the internet.

I've had the playfield lifted and have worked on the underneath, but this is the first pinball I've ever really worked on, so I'm not up to speed on some of your terminology (like when you say 'smart switches', I'm not sure what that is).  I have had the offending drop target bank off of the back of the playfield and cleaned it all out and sanded the contacts, and checked to see it was working properly (mechanically) and as far as my untrained eye can tell, it seems to be working good mechanically.  I have seen the board that lilshawn is talking about (it's a beige board instead of green, up near the front of the playfield, I'll have to see if I can take it off and find the right diodes for it, thought I would see if anyone of you more experienced guys knew off the top of your head what kind to use in it's place, but I figured it was a long shot (you never know though).  I have actually already replaced one diode on my pricess LED shroud on the playfield (the one that counts your multi-ball status).  It was missing a diode (didn't have a broken one on there to compare so I found it in a book which one it needed).  I actually checked mouser on that one first, and didn't find what I wanted right away, but then thought I should check some pinball vendors and was able to find it from bay area amusements (it was a 5 watt 120 ohm diode if I remember right, they were only $2ish, not bad, and it fixed the shroud lights so they work perfectly now).

[lilshawn]

you should be able to replace them with just a standard 4004 diode...don't quote me...the old diodes should have a number printed on them...just match the number.


i've picked up a 100 pack of 4004's for about 12$