Fathom - Random solenoids firing and weak solenoids

[mattmorphett]

Hey all,

I haven'y played My Fathom for quite a while (criminal I know) and I recently switched it on to discover that the right upper flipper wan't working.  On closer inspection the OES switch was burned out.  I replaced it and I believe it is all working correctly there now.

... but I have another problem and I'm not sure if this problem was there before or only occurred after replacing the EOS, but...

is doing some weird things - sometimes they appear as soon as I switch on, sometimes it take a little delay:
- Coils are randomly firing while I play - bumpers, cabinet knock, new ball elevator, right side captive ball ejector (pops it out behind the targets where it gets stuck).
- Solenoids are weak - it gets to the point where it can't bring the new ball up into the plunge lane and it can't reset the targets.
- Flippers are available in attract mode!

Any ideas?  Or places to check and measure?

Thanks.
Matt.
PS. In other news, my buddy bought the Tommy from Marty - I can't wait to see it.

[mildflame]

I thought it might have been a missing ball problem... not too sure whats going on there
until you said the flippers are active in attract mode.
the flippers should be a different problem from the random solonoids firing
The flippers could be a stuck relay, give all the relays a flick and try again, it the relay is stuck then the flippers will say active, (found that out a few weeks ago on Williams Flash )
It seems like a real thinker
I'm sure someone can help you!
  To aussiepinball by the way!

[Strangeways]

There a small PCB under the playfield - soldenoid expander board - remove and check for dry joints. There is also a 555 globe in the vicinity. If that is not working, then you will have strange issues like this.

Second thing to try is to reseat the connectors to the Solenoid Driver and MPU

Third thing to try is reseating the PIAs on the MPU - U10 and U11.

You can run a simple test with the game on - the "test" button on the front door. Cycle through to the solenoid test and check that each solenoid is working during test.

[swinks]

Not wanting to add confusion, but on my Skateball I had some strange issues not similar to this but still one that wasn't obvious as it was the processing chip. Could a chip be gone on the MPU that puts it into a solenoid test mode ?

[mattmorphett]

Oh, noes...

I reseated the PIAs and ROMs on the MPU.

Reflowed the header pins on the MPU board and on the solenoid driver board and reseated the connectors.  Feflowed a couple of IC sockets while I was there.

Now I only get 1 flash on the MPU.

: (

Pulling boards out and rechecking work.

Thanks for your help so far guys.
Matt.

PS. I'm pretty sure the expander is good and I replaced that globe last week.  But I'll check it all again once I get the machine booting again.

[mattmorphett]

Well, I've definitely broken it : (

I only get 1 flash, sometimes 2 which looks the RAM has gone bad. 

I imagine I have done something while reseating or reflowing U7 or U8.

There is a fair bit of battery corrosion down there and some of those joints look a little crusty.  I cut out the old battery and installed a new one when I bought this 8 years ago.  Looks like this one might have leaked too.  I have cut it off and cleaned up as best I can without removing components.

It looks like I have done a reset circuit rebuild and an HV rebuild on it - was a while ago but it rings a bell.

So I have at least 2 problems, possibly more and many signs are pointing to the MPU.

I think I might be ordering one of those Alltek Ultimate MPUs.  What do you think? Have I given up too easily?

It looks like those Ultimate MPUs are pretty much plug and play after you have set DIP switches.  Does anyone have any experience with them?

My only other option is that a friend has a Xenon.  I guess I could put the RAM etc in his and see if it boots. 

Any other thoughts?

Thanks.
Matt.

[goodolddays]

Gday Matt . I noticed the other day that Mark C has some some NOS Ultimate MPU boards if you decide to go that way for $254..

http://www.pinballspareparts.com.au/index.php?crn=273&rn=811&action=show_detail

Cheers
Dave

[goodolddays]

or a cheaper option from Mike (Homepin)

http://aussiepinball.com/index.php?topic=6507.0

[swinks]

Or another option is some chips for your MPU - contact Skybeaux, you never know it could be something small and cheap.

[mattmorphett]

Some good suggestions there for keeping the cost down but, y'know, I'm past the point of "This is fun and I'm happy to spend many more hours to save a hundred bucks or so".  Throwing the towel in and buying the Alltek from Mark. : )

That will at least get me a board that boots and will hopefully solve to original problem too. 

Thanks for your help so far.

I'll let y'all know how it goes once the new MPU is in.
Matt.

[Strangeways]

"I only get 1 flash, sometimes 2 which looks the RAM has gone bad.

I imagine I have done something while reseating or reflowing U7 or U8."

Not necessarily - You have a fault and by removing the Chips, you have just highlighted it. I would not waste money on an Altek, as I think all you really need to do is remove each chip, look for bent legs and give them a light sand with 360 Grit sandpaper.  You could literally be 5 minutes away from having a trouble free board for years. I've seen dozens of boards not booting and then simply cleaning and reseating Chips fixes the problem.

[mattmorphett]

Thanks for the encouragement, I definitely appreciate it.

I abbreviated a few steps in that last post.

I pulled the board 4 or 5 more times and went through the following:
- Pulled all the chips 1 by one and gently wire brushed and washed down the pins with alcohol so they looked all shiny.
- I reflowed the sockets down where U7, U8 and U11 are - as best I could with the corrosion residue causing some problems there.  
- I then straightened the pins in the ICs and re-inserted them.

As I did this I noticed that 1 of the pins on U6 (which was an original Bally IC) had (at some point before me) broken off and someone had soldered on a new leg: Piggy-back style.  It looks reasonably serviceable.

I also noticed that one of the legs on U7 was a little wobbly.  I gingerly put it back into the socket but I daren't remove it again : (

I think there is a good few more hours of messing about ordering and trying chips etc. and the more I look at the corrosion the more I think I'd need to do that reset section - again.

Even after all of that, if I get it to boot, I might still have the intermittent problem that I was originally trying to solve.  I have a hunch (possibly unfounded) that those random and weak solenoids were something to do with that MPU board.

At this point, with my day job I can earn more in 1/2 a day than I could save diagnosing and fixing for another half a day continuing down this path with the chips and I'd still have to buy new chips, socket, reset section, etc, etc.

I know it isn't about the money but I'm tired, beaten and I just want to play my pinball, not tune it's dang carbies : )

Besides I'm about to sink more time than I could ever "fathom" into this project...

http://australianairstream.blogspot.com/

Thanks for the help and encouragement guys.  I may be back if the Alltek doesn't fix my original intermittent problem :)

Matt.

[Marty Machine]

Interesting prob, although i can't help thinking it's more to do with power-supply not the mpu board.

While the voltages *might* be correct, i'm sure something is giving out under load, hence the 'weak' flippers...
the 60volts dropping to 20v or something? or the 5v regulation failing and droping to 4v etc....

Is there DEFINATELY 5v on the MPU board, and CPU?

I'd hate you to fork out on a new MPU board only to find it's your power supply that's causing the probs.

MM.

[mattmorphett]

I'm getting 5.12V at TP1 on the solenoid driver board.

Maybe I should check the MPU board itself.

The flippers themselves haven't ever been weak (I don't think).  They still kick just as hard as ever. It is other solenoids that have the problem - i.e. anything that is "driven" by the boards.

I reflowed all the connectors and recs on the powersupply board a few days ago and test points and seem pretty close on.  If fact I reflowed nearly every joint on the dang board down there.

The fact that it was allowing the flippers on (at full strength) during attract mode and randomly firing coils makes me think that something is wrong with the MPU.  It sounds like screwy control messages coming through - but I guess you are right, voltage weirdness can do weird things too.

i've put in an order with Mark for the Alltek.  We'll see how that goes.

...but don't let that stop the suggestions.  

Thanks.
Matt.

[Marty Machine]

I'm getting 5.12V at TP1 on the solenoid driver board.
Maybe I should check the MPU board itself.

Yep! a LOT can happen to the voltages in between boards, loose connectors, poorly crimped pins, corrosion and burn out etc....
While the Power supply might have 5v-12v leaving it, it doesn't mean the mpu (& other) boards are receiving 5v-12v  ;-)
It's always best to measure on each of the boards, as most boards have their own voltage regulators and associated components which can fail....

The flippers themselves haven't ever been weak (I don't think).  They still kick just as hard as ever. It is other solenoids that have the problem - i.e. anything that is "driven" by the boards.

Flippers are typically on a different voltage supply to the playfild solenoids, and flippers are not (never?) controlled by the driver board, so that would highlight the different 'kick' they have....

anyway, good luck with the new board, at least it will definately prove your old mpu (or not).

MM.