Williams Flash problem

[chris288]

Hi All,

Got a bit of a problem with a Flash I'm restoring for my brother in law and wondering if anyone here can shed any light on where the problem might be.

Ok, the MPU and driver boards were so badly acid damaged they were beyond economical repair so I have installed a brand new Rottendog combined MPU/Driver board and also a brand new Rottendog power supply board.

The problem is that when a game is under way the machine resets or tilts .
Sometimes you lose only the ball in play other times you lose the whole game and it goes back to attract mode.

Trying to fault the machine I found there are 3 switch stacks located just above the RHS top flipper. They are similar to slingshot switches and are referred to in manual as right side standup switch upper, center and lower.

Whenever I touch the lower switch it always ends the game . Whenever I touch the others it will end game sometimes but not always , but also touching the switches on the 2 drop target banks will end the game too, not straight away but usually after 2 or 3 drops.

I dont have a circuit diagram for this but did look at Clays repair site which suggested such resets are usually related to power supply or coil diode problems.

The power supply is new so I assume that all ok. I have checked all diodes associated with those switches and also tilt switches and they seem to be ok.
When a reset happens the Tilt light comes on so I assume that the switches are part of the tilt circuit as well.

Has anyone had any similar problems like this? or maybe suggest where to look next?

Chris

[Strangeways]

Question - Did you replace the headers and pins ?

I would start by repinning the switch matrix connector to the Driver board. Yes - I've seen similar problems with the switch matrix causing havoc. You could even try pushing each individual wire on that connector while a game has started and see if it resets.

Resets are common on these games and are always an issue with the power supply - they usually reset when BOTH flipper buttons are pressed simultaneously.

[chris288]

No, have'nt replaced headers or pins, will give that a try when I get a spare minute.

The reset doesn't happen when flippers are used, only when certain switches are activated.

Thanks for the tip Nino, I will update here when I have solved it.

[MartyJ]

No, have'nt replaced headers or pins, will give that a try when I get a spare minute.

The reset doesn't happen when flippers are used, only when certain switches are activated.

Thanks for the tip Nino, I will update here when I have solved it.

Chris,

Couple of things.

Did you remove the middle bracket (which use to sit on the top edge of driver board?

Also on the r/h/s of the rottendog board - from memory it doesn't use the middle screw hole.  The factory bracket is three holes and it may be grounding out part of your switch matrix.  If its there I'd cut the hole off the bracket (if this makes sense)...

[FirePower]

Chris, here's a few thoughts that may assist or narrow down the problem?

I'd first isolate what is causing the problem, could be board related or play field related.  With new boards it's unlikely to be a board fault, but it could be installation issues like Marty has mentioned.  So disconnect switch row and col inputs and test the board side. Clay's guide has a description on how to do this with diagnostic mode and an alligator lead.  I'd guess this will all be ok, but best to prove it.

With the playfield plugs removed give them a really good visual  examination - I use a big magnifying glass. For a few bucks and an hour or so repin them, Same detailed close visual  examination of all switches - you're looking for blobs of solder or whiskers of wire that are out of place. In desperation you could replace all switch diodes., but this is only really an issue for simultaneously closed switches.

In diagnostic mode with play field connected I'd repeatedly exercise the switch that are causing the resets and examine which switch shows up.  If it's not the correct one that should give you some leads. 

With a game up I'd fire all the solenoids a few time each, one at a time - if no resets occur I'd say this rules out power supply issues.

I take it you've got the game manuals?  The firepower site www.firepowerpinball.com has wiring diagrams and just use the switch matrix table in the manuals for equivalence.

In normal game operation does slam tilt cause a total game over, whereas pendulum tilt looses just a ball?  I don't know but am wondering about the different resets going on?

Hope this gives you a few ideas.

[chris288]

No, have'nt replaced headers or pins, will give that a try when I get a spare minute.

The reset doesn't happen when flippers are used, only when certain switches are activated.

Thanks for the tip Nino, I will update here when I have solved it.

Chris,

Couple of things.

Did you remove the middle bracket (which use to sit on the top edge of driver board?

Also on the r/h/s of the rottendog board - from memory it doesn't use the middle screw hole.  The factory bracket is three holes and it may be grounding out part of your switch matrix.  If its there I'd cut the hole off the bracket (if this makes sense)...

Yes, Marty bracket was removed long ago, but I do see what you mean about the middle screw hole on the RHS bracket grounding out the board. Rottendog just put a blob of silicone under the header to insulate it. Thats not good enough in my book so have removed the middle "tab"altogether.

Chris, here's a few thoughts that may assist or narrow down the problem?

I'd first isolate what is causing the problem, could be board related or play field related.  With new boards it's unlikely to be a board fault, but it could be installation issues like Marty has mentioned.  So disconnect switch row and col inputs and test the board side. Clay's guide has a de******ion on how to do this with diagnostic mode and an alligator lead.  I'd guess this will all be ok, but best to prove it.

With the playfield plugs removed give them a really good visual  examination - I use a big magnifying glass. For a few bucks and an hour or so repin them, Same detailed close visual  examination of all switches - you're looking for blobs of solder or whiskers of wire that are out of place. In desperation you could replace all switch diodes., but this is only really an issue for simultaneously closed switches.

In diagnostic mode with play field connected I'd repeatedly exercise the switch that are causing the resets and examine which switch shows up.  If it's not the correct one that should give you some leads. 

With a game up I'd fire all the solenoids a few time each, one at a time - if no resets occur I'd say this rules out power supply issues.

I take it you've got the game manuals?  The firepower site www.firepowerpinball.com has wiring diagrams and just use the switch matrix table in the manuals for equivalence.

In normal game operation does slam tilt cause a total game over, whereas pendulum tilt looses just a ball?  I don't know but am wondering about the different resets going on?

Hope this gives you a few ideas.

Thanks David that helps quite a bit.
Have tried firing all solenoids manually and that seems ok, but one pop bumper activates itself and its neighbour while the neighbouring pop bumper does the same. The third one is all ok and fires only itself. Not sure whats going on there.

Did the diagnostics check and most switches come up ok, but  2 of the rhs standup switches wont indicate at all when manually closed and heres the funny thing, everything else on the same column doesn't register either eg eject hole, a few drop targets etc.

In the Flash manual they are all listed as being in the 4th column and the common wire being a Green/Yellow.
I traced that back to the header in the backbox and that all seems to be ok ie: no breaks so, not sure where to go next.

If there was a stuffed diode in that chain would that be likely to cause all those switches to not indicate during diagnostics check?

[Strangeways]

I'd be changing the diodes in that row - as you have highlighted. Quick and easy. Make sure that common wire to that row has no breaks - which I think you have done already.

[FirePower]

Wow - too many problems happening at once here,

1. Solenoids first.  They work with the special solenoid circuit - top left connector on driver board. On the bumpers there are two switches. the one on the spoon does the firing, The lower - furthest from the pf is for scoring which is via the switch matrix.  Is vibration causing the adjacent solenoid to fire - visually examine the spoon switch gaps.  Stick a piece of paper between the adjacent ones to test if  it's vibration.   You can also disconnect the playfiled plug at the driver board and test directly to the driver board pin.

2. Switch matrix. Did you verify normal operation of the driver board without the playfield connected as suggested?
Note the upper right standup is in a different col.  If the driver works on its own then look very carefully over the 3 bank drop setup as this is common to the col.  You can easily undo and remove the three drop target circuit boards for examination.

I'm not convinced that replacinging diodes will help at this stage - for it to be a faulty diode two things must simultaneously occur; firstly the diode must fail closed and secondly the corresponding switch must be closed .... lotto time?

[chris288]

Wow - too many problems happening at once here,

1. Solenoids first.  They work with the special solenoid circuit - top left connector on driver board. On the bumpers there are two switches. the one on the spoon does the firing, The lower - furthest from the pf is for scoring which is via the switch matrix.  Is vibration causing the adjacent solenoid to fire - visually examine the spoon switch gaps.  Stick a piece of paper between the adjacent ones to test if  it's vibration.   You can also disconnect the playfiled plug at the driver board and test directly to the driver board pin.

2. Switch matrix. Did you verify normal operation of the driver board without the playfield connected as suggested?
Note the upper right standup is in a different col.  If the driver works on its own then look very carefully over the 3 bank drop setup as this is common to the col.  You can easily undo and remove the three drop target circuit boards for examination.

I'm not convinced that replacinging diodes will help at this stage - for it to be a faulty diode two things must simultaneously occur; firstly the diode must fail closed and secondly the corresponding switch must be closed .... lotto time?

Thanks David, I think you are right it may be vibration. Will do that check tomorrow.

Secondly, no I didn't do the driver board/ alligator lead test yet because I assumed that being a new board it was more than likely it would be ok, but I will go and check the 3 bank drop targets first and then do the driver check.
 It may be the weekend before i can spend any decent length of time on it though.

But thanks heaps guys for helping us out here, really appreciate it.

[FirePower]

Secondly, no I didn't do the driver board/ alligator lead test yet because I assumed that being a new board it was more than likely it would be ok, but I will go and check the 3 bank drop targets first and then do the driver check.

I think you'd be better to verify the driver side first, I wouldn't go as far as to say you're crazy if you don't, but ....  It must work for everything else to be ok, it's a pretty quick and easy test that will aide your understanding and allow a decent visual check of the plugs which is also necessary.  Yes, it's a new board, but infant mortality is not unheard of.  If it passes then you have immediately narrowed down your field of search for the problem.

Another thing you can do is with the driver switch matrix connectors removed and the all the drops up. ejects and ball trough empty then use a multimeter to test for continuity between col 1 and each row. Then move to col 2 and again step through each row and so on.  You should see open circuit between everything. Any short circuit is an area for investigation.

[chris288]

Ok I checked the driver switch matrix connectors between columns and rows and everything came up open circuit, so no shorts there.

Secondly I did the diagnostics test with the alligator lead and all the switch numbers were coming up fine until I got to pin6 on the 2J2 header.
Before then just 1 number would appear and then sequentially decrease as I moved down the header as it should indicating that particular switch number, but shorting out pin6 on the 2J2 header with any pin on the 2J3 header would give all sorts of odd numbers , but then move the alligator lead down to pin 7 on the 2J2 header and then the sequential decreasing of switch numbers would continue again all the way down to 1.

So , it would appear to be a fault with the board.
A visual inspection came up all ok, no broken tracks or shorts on the board.

So, not sure what to do next. Rottendog are closed until after the pinball show, but I guess next thing will be to email them and ask if theres anything else I can do.

[Strangeways]

Ok I checked the driver switch matrix connectors between columns and rows and everything came up open circuit, so no shorts there.

Secondly I did the diagnostics test with the alligator lead and all the switch numbers were coming up fine until I got to pin6 on the 2J2 header.
Before then just 1 number would appear and then sequentially decrease as I moved down the header as it should indicating that particular switch number, but shorting out pin6 on the 2J2 header with any pin on the 2J3 header would give all sorts of odd numbers , but then move the alligator lead down to pin 7 on the 2J2 header and then the sequential decreasing of switch numbers would continue again all the way down to 1.

So , it would appear to be a fault with the board.
A visual inspection came up all ok, no broken tracks or shorts on the board.

So, not sure what to do next. Rottendog are closed until after the pinball show, but I guess next thing will be to email them and ask if theres anything else I can do.

Hopefully they can advise on a simple fix rather then a return to base warranty.

[FirePower]

Off course if you'd done the tests in "correct" order you'd have saved yourself a few minutes, but ok that's enough of me being a smart arse  and I promise this the last time I'll mention this!

I'm not familiar with the Rottendog boards, but I'd guess the switch area is fairly similar to the originals. They probably use different row switching transistors to dump the 5W resistors and the predrive transistors (this is a fairly standard upgrade even for old driver boards), but the circuit behind this will probably be the same.  If the chips are socketed you could try and swap a few around to sort out if the fault is chip or board / track related.  The switch PIA and associated buffer chips are the ones I'd swap if I could.  In the original WMS design they are IC10 the PIA, IC13 & IC14 the col buffers and IC19 & IC12 the row buffers.  It's probable the buffers aren't socketed so you may not have that option.

Do you have a schematic for the board and can you post up a snippet showing this area?

[48]

Secondly I did the diagnostics test with the alligator lead and all the switch numbers were coming up fine until I got to pin6 on the 2J2 header.
Before then just 1 number would appear and then sequentially decrease as I moved down the header as it should indicating that particular switch number, but shorting out pin6 on the 2J2 header with any pin on the 2J3 header would give all sorts of odd numbers , but then move the alligator lead down to pin 7 on the 2J2 header and then the sequential decreasing of switch numbers would continue again all the way down to 1.

So , it would appear to be a fault with the board.
A visual inspection came up all ok, no broken tracks or shorts on the board.

Mate, pin 6 is the key pin on 2J2 on the Rottendog board as far as I can tell.
I assume it shouldn't be tested as it would give strange readings.

[48]

BTW  did you replace those Molex connectors? The crap I have been going through with mine is crazy.
I just do em as soon as a fault appears on the switch or lamp matrix now (thanks Nino and Daniel)
Of course the header pins are new on the new board.