Pinbot display ALL OUT

I'm restoring a Pinbot with corrosion problems due to a battery leakage. As part of the process a great part of components has been replaces with brand new ones!

Before starting the restoration the machine would play but with the display flicking segments on and off making it nearly impossible to read the content. I took off all cables and wires to the MPU board and sprayed the connectors with a liquid made for cleaning PCB. I then attached cables and wires and turned the game on. But now the entire display died.

I didn't pay much attention to it at that time because I knew I had to rework the entire board and hoped that would fix the problem.

Now I'm done changing all the components. The machine will boot. The 5v+ and blanking LEDs are on and the diagnostic LED is flashing. When booting it starts by sounding 5 beeps - which I believe is a sound board issue and then it will play the "famous" dong letting you know the system is up running.

I checked for continuity on the board - which seams to be fine. I checked the pins on J22 and they all have "signal" some of the change hi / low more frequent than others. I also tried to test the connection from the MPU board to the display board. No cigar !

Please note that the display was changed to LED. So it's not the original display I have installed in my machine.

So - what's next I think? Where would you go from here ?!?
I'm thinking that it's NOT the display that has gone all bad - or ?!? I mean - them all at once ?!?

Wow - totally out of ideas, so I hope you can help !!

#2 7 years ago

DAV

wayout440

Pinside member

OP
Quoted from mcklit:
I'm restoring a Pinbot with corrosion problems due to a battery leakage. As part of the process a great part of components has been replaces with brand new ones!
Before starting the restoration the machine would play but with the display flicking segments on and off making it nearly impossible to read the content. I took off all cables and wires to the MPU board and sprayed the connectors with a liquid made for cleaning PCB. I then attached cables and wires and turned the game on. But now the entire display died.
I didn't pay much attention to it at that time because I knew I had to rework the entire board and hoped that would fix the problem.
Now I'm done changing all the components. The machine will boot. The 5v+ and blanking LEDs are on and the diagnostic LED is flashing. When booting it starts by sounding 5 beeps - which I believe is a sound board issue and then it will play the "famous" dong letting you know the system is up running.
I checked for continuity on the board - which seams to be fine. I checked the pins on J22 and they all have "signal" some of the change hi / low more frequent than others. I also tried to test the connection from the MPU board to the display board. No cigar !
Please note that the display was changed to LED. So it's not the original display I have installed in my machine.
So - what's next I think? Where would you go from here ?!?
I'm thinking that it's NOT the display that has gone all bad - or ?!? I mean - them all at once ?!?
Wow - totally out of ideas, so I hope you can help !!

Have you tried replacing the ribbbon cable? Cleaning will only, possibly work if oxidation is the problem. Cleaning will do little to help worn out connections in the connectors.

Ideally, the best action would be to test the system with a known good display and ribbon cable. If you had the original display (I assume you probably don't) that would be something to test with.

#3 7 years ago

ARS

thedefog

Pinside member

If it isn't the ribbon cable, perhaps the SIP pack by the display IC got nailed by the corrosion. That, or the display decoder IC.

#4 7 years ago

WTS

WonkoTSane

Inactive member

9y 44,150 655 43

Remember that battery corrosion is not just contained to the board with the batteries. It can be spread through wires as well as the gasses that are expelled by the leaking battery. The gas is heavier than air and will sink to the bottom of the back box. Check for corrosion on any boards near the bottom.

#5 7 years ago

HKA

mcklit

Inactive member

Quoted from wayout440:
Have you tried replacing the ribbbon cable? Cleaning will only, possibly work if oxidation is the problem. Cleaning will do little to help worn out connections in the connectors.
Ideally, the best action would be to test the system with a known good display and ribbon cable. If you had the original display (I assume you probably don't) that would be something to test with.

Tried changing the ribbon cable and it made no difference.

No- unfortunately I don't own a spare display I can test with. That would have been great though!

#6 7 years ago

HKA

mcklit

Inactive member

Quoted from thedefog:
If it isn't the ribbon cable, perhaps the SIP pack by the display IC got nailed by the corrosion. That, or the display decoder IC.

I changed all SIP resistors that connects with U41 and U42 (IC PIA). So they are brand new.

What is the difference between the "display IC" and the "decoder IC" ?

#7 7 years ago

HKA

mcklit

Inactive member

Quoted from WonkoTSane:
Remember that battery corrosion is not just contained to the board with the batteries. It can be spread through wires as well as the gasses that are expelled by the leaking battery. The gas is heavier than air and will sink to the bottom of the back box. Check for corrosion on any boards near the bottom.

Ok - good informationer !

But the MPU board is the lowest PCB in the backbox so I guess that the others boards are none suspects in this problem?

#8 7 years ago

WTS

WonkoTSane

Inactive member

9y 44,150 655 43

OP
Quoted from mcklit:
I changed all SIP resistors that connects with U41 and U42 (IC PIA).

If you replaced the resistor matrices, did you make sure to align the new ones correctly? They are directional. One end will have a dot that needs to go in the same direction as the old one.

#9 7 years ago

HKA

mcklit

Inactive member

I am quite sure I aligned them correct as I paied extra attention to installing this pack. The reason being the missing leg on pin 10 which is not needed since the resistor network are without a "build in" capacitor.

Can the missing capacitor be a problem? I read somewhere that I could order the resistor SIP without a capacitor !!

But - no matter what ! When I get back home I'll check again to make sure they are aligned correct.

#10 7 years ago

DAV

wayout440

Pinside member

OP
Quoted from mcklit:
I am quite sure I aligned them correct as I paied extra attention to installing this pack. The reason being the missing leg on pin 10 which is not needed since the resistor network are without a "build in" capacitor.
Can the missing capacitor be a problem? I read somewhere that I could order the resistor SIP without a capacitor !!
But - no matter what ! When I get back home I'll check again to make sure they are aligned correct.

The missing capacitor is not a problem, it is common to replace these with resistor only SIP networks. You just need to make certain that bussed resistor networks are replaced with bussed resistor networks and isolated resistor networks are replaced with isolated resistor networks. Bussed resistors use a common pin indicated at the dot or marked end of the package.

You've addressed most of the "easy" stuff. It would be really nice to confirm that your cable and display are working in another machine, just to be certain that you are dealing with a board problem. Corrosion is possibly your phantom, as the damage is sometimes not visible. It could be a problem with one of the PIAs.

Does your LED display have some kind of test button on it? I've heard that some do.

#11 7 years ago

HKA

mcklit

Inactive member

Well - that's a good argument when dealing with my wife about getting one more pinball But I'm afraid that I only have one pinball with a system 11 board. My STTNG will not do me any good here I guess. So testing the display on another machine is unfortunately not an option.

I'll look when I get home to see if there is a test button on the board.

As part of the restoration I changed a LOT of components on the board. 3 of them where PIAs (U41, U42 and U51). So they are brand new and most likely not the cause of the problems I guess. U41 and 42 are part of the components involved in sending data through jumper J22 (with the ribbon cable to the display board).

If i disconnect the ribbon cable and use my logic probe to find activity on the pins on J22 I can see that in fact there is ata send this way.

So it looks like the MPU board is working but I do not get anything up in the display.

I tried searching for the schematics regarding the PINLED item no: 10015 so I might have that at hand when fail searching. But I had no luck finding it.

Thinking about it, I should probably measure the voltage again on the input to the display PCB. Do you agree that it should read +5v ?

#12 7 years ago

DAV

wayout440

Pinside member

OP
Quoted from mcklit:
Thinking about it, I should probably measure the voltage again on the input to the display PCB. Do you agree that it should read +5v ?

Yes, the logic power input on the original board is 4J11 pin 1 ground and pin 6 +5VDC. Of course, being LED you'll ignore high voltage pins 3 & 4, all you care about is the logic power making it to the alphanuemeric display board.

#13 7 years ago

JAH

heni1977

Pinside member

Decatur, IL

11y 89,800 2,529 4 6

Is the ribbon cable installed properly. I had a issue with my space station with flickering segments and some not even coming on. Reversing the ribbon cable at the cpu fixed the issue. I too took my board out and sent off to fix corrosion. When I put back in I hooked the ribbon cable up backwards

#14 7 years ago

SLM

Slim64

Pinside member

9y 61,550 2,034

The taxi I picked up had a "dead" display, turns out the ribbon cable was reversed. Make sure the red wire is on pin 1

#15 7 years ago

ARS

thedefog

Pinside member

OP
Quoted from mcklit:
What is the difference between the "display IC" and the "decoder IC" ?

Same thing. Sorry for the confusion. Decoder IC.

Do you have a logic meter or a scope? That'll let you know what is going on with the output to the displays. With a DMM, you'll at least be able to identify stuck pins in H/L states.

#16 7 years ago

HKA

mcklit

Inactive member

Sorry for the late feedback. I had a business trip that took up my pin-time

I tried exchanging the ribbon cable and also flip it even though it was already mounted correct. No result.

Also took a reading on the pins on j22 and they are "active". But can any of you tell me, if one or more pins are vital to be either high or low to make the display work? I mean - does it have some sort of "master pin / enabler" that needs to be either constant high or low that I should pay special attention to? Or maybe one ore more pins that CAN NOT be stuck on either high or low to make the display work?

Another thing I need to get out in the open - I blew it! I messed up big time! Thought I would just look at the display board and didn't care to switch of the machine. A 3 second buzz sound and a boom followed by a spark flying of the board tells me I shortened something. Most likely a capacitor I would guess. My problem is that I can't find from where the spark came flying and a visual inspection do not show any damage.

This setback will keep me busy for some time till I find what has been shortened

But - even with the display off the MPU board, I still can measure pin activity on j22. So keep all your input coming and I'll post the feedback here.

Arrrrrgh !!

#17 7 years ago

ARS

thedefog

Pinside member

OP
Quoted from mcklit:
Also took a reading on the pins on j22 and they are "active". But can any of you tell me, if one or more pins are vital to be either high or low to make the display work? I mean - does it have some sort of "master pin / enabler" that needs to be either constant high or low that I should pay special attention to? Or maybe one ore more pins that CAN NOT be stuck on either high or low to make the display work?

You've done basically all you need to do, just looking at the output pins and looking for activity to make sure the 74154 isn't dead from corrosion. But since it was working prior with flickering, the MPU is probably ok. So rule that out. Move on from there.
74154_(resized).png

As far as your display board blowing out, if you shorted the +90v/-100v to a logic section, you may have toasted the logic on the board, depending on where you shorted it. Hopefully not, but at least display boards aren't expensive to replace. There are no large electrolytic filtering caps on the display board, so not a cap issue on that board. Assume it is destroyed at the moment and focus on the PSU now.

It is highly likely your HV section blew out when you shorted it. That's what they do when you cross the streams. Do you feel confident enough to test the HV section on your PSU with a meter? If not, don't do it.

I am willing to bet the flickering issue is also due to dried up HV section caps on your PSU. I've seen that before. Time for a HV section rebuild on there. If you don't feel comfortable doing that, there are plenty of people that can do it on here.

And don't sweat blowing it up, as long as your learned something from it (don't mess with the HV section while the game is on).

If I were you, I'd buy an xpin display and move on. $200 will solve all your issues at once. No more HV section & a new display board to rule that out. Sell your old glass to help with the costs.

#18 7 years ago

HKA

mcklit

Inactive member

The 74154 (U44) was changed a part of the repair. It had severe corrosion on multiple legs and needed to be replaced. I bought a 74LS154 as replacement which I think should be ok ?

Regarding the shorted pins - I'm quite sure it's not +90/-100. I already have a LED display installed. As part of the installation fuse F1 in the PSU was removed. So I believe the board only receives +5v. But in Pinbot the display board is located in plastic pins hovering over some metal wires that supply power to the bulbs in the back box. It might be that I somehow touched the wires with the board.

Hmmm - not sure what to do next....

#19 7 years ago

ARS

thedefog

Pinside member

OP
Quoted from mcklit:
The 74154 (U44) was changed a part of the repair. It had severe corrosion on multiple legs and needed to be replaced. I bought a 74LS154 as replacement which I think should be ok ?
Regarding the shorted pins - I'm quite sure it's not +90/-100. I already have a LED display installed. As part of the installation fuse F1 in the PSU was removed. So I believe the board only receives +5v. But in Pinbot the display board is located in plastic pins hovering over some metal wires that supply power to the bulbs in the back box. It might be that I somehow touched the wires with the board.
Hmmm - not sure what to do next....

Yep, no HV on LED. What manufacturer LED displays do you have?

#20 7 years ago

ARS

thedefog

Pinside member

https://en.wikipedia.org/wiki/7400_series

OP
Quoted from mcklit:
I bought a 74LS154 as replacement which I think should be ok ?

Just read this. The LS version may not work right in this instance. You need to use the standard TTL, not a low power CMOS version or any other marking (Like HC, HCT).

The reason being is that the switching speed in the CMOS versions is slower, hence the strobing effect you're seeing.

#21 7 years ago

HKA

mcklit

Inactive member

Link: http://shop.pinled.de/product_info.php?cPath=2_3_58&products_id=20

It is from PINLED

Ok - just to be clear. When you say HV you mean High Voltage - right ? So you are suggesting that there should be a High Voltage area on the display board on my LED display. Or maybe I get it wrong?

With fuse F1 out of the PSU there should not be any HV send to the display board. Or ... ?

Tried to locate the schematics for the PINLED board - but no luck!

#22 7 years ago

ARS

thedefog

Pinside member

OP
Quoted from mcklit:
It is from PINLED
Link: http://shop.pinled.de/product_info.php?cPath=2_3_58&products_id=20
Ok - just to be clear. When you say HV you mean High Voltage - right ? So you are suggesting that there should be a High Voltage area on the display board on my LED display. Or maybe I get it wrong?
With fuse F1 out of the PSU there should not be any HV send to the display board. Or ... ?
Tried to locate the schematics for the PINLED board - but no luck!

No Fuse F1 for LED displays, you're correct. You don't need a HV (high voltage) section for them. They're powered entirely by the +5v section.

I'd replace your 74LS154 Decoder IC with a TTL 74154 (no markings) first. That'll solve the strobing issue you were having. Then, as far as the PINLED board goes, it is likely they don't offer schematics for it. So unfortunately, you'll have to debug it without schematics if it still doesn't work, or possibly send it back to them for repair or order a replacement.

Take a picture of the front of the board and I'll try to help with where you can poke around with a meter to figure out what got fried on the board (if anything did) if you want to try to repair it yourself. Start with the replacement decoder IC on the MPU first.

#23 7 years ago

HKA

mcklit

Inactive member

Been searching for at TTL 74154 but they are not easy to find in DK. So getting one will mean high freight and most likely tax on top.

Before I go that way, I would like to explore my other options.

Is there no other way to test if the display is ok? I mean - can I somehow pull a wire directly from the MPU to the display board and see if that makes a difference? It would be fine simply to see one of the segments in one of the displays light up just to confirm that it's capable of that ?!

Just an (crazy ???) idea?

1 week later

#24 7 years ago

HKA

mcklit

Inactive member

To everyone following this thread - I haven't forgotten about it. By coincident I found that the blanking signal is always low and it's not changing. So I started another thread about the blanking signal to figure out what that does because I had an idea about this being wrong.

Once I know more about the blanking signal issue, I'll continue this thread to keep you all updated and most likely ask more questions

I'll be back

#25 7 years ago

HKA

mcklit

Inactive member

Ok - so nothing wrong with the blanking signal. Turns out it's doing exactly what it's supposed to do. But an important lesson was learned. If you want to know more about the blanking signal and what it is used for, you can find some very good insight here: https://pinside.com/pinball/forum/topic/what-is-blanking-signale-used-for

Back to my topic !!

I bought an oscilloscope to learn more about the signal send out through the pins on J22. Looking closer I found that 5 of the pins NEVER was high which I thought was strange.

Combined with the input early on in this thread about how sensitive the ribbon cable is, I went on to replace J22 connector on the PCB. In the same process I changed the ribbon cable.

AND NOW THE DISPLAY HAS COME TO LIFE

It's still not showing the right figures and letters - but it's close. So you can make out what the display is trying to show, but it still needs some fixing to get it right.

I don't know what can cause the display to "mess up" the letters. E.g. "A" can become "8" or "1" can become "7" and so on.
I'll have to look into this and see if I can figure it out.

All inputs are welcome !

#26 7 years ago

DAV

wayout440

Pinside member

Ribbon cables are notorious. Chances are high that the male header pins have oxidation and this may be causing the lack of a certain signal, which results in the garbage display readout.

#27 7 years ago

HKA

mcklit

Inactive member

Quoted from wayout440:
Ribbon cables are notorious. Chances are high that the male header pins have oxidation and this may be causing the lack of a certain signal, which results in the garbage display readout.

You can say that again !!

Turned out they where the last bump to solve in this quest to get the display back on !

One important lesson to learn from this is - ONLY TEST ONE RIBBON CABLE AT A TIME

I had all cables in at the same time, but I decided to remove all cables except one so I could focus on what segments where on and off one display at a time. As I removed all cables except one, it turned out that the one display left to be tested worked just fine !!! So I tried moving the cable, exchanging positions adding and removing more cables and displays. At a point it was clear to me that all by cables except one was faulty !!

The hard part to learn this is, that if you have a working cable and you insert a faulty cable it WILL INFLUENCE the working cable. So you might think both cables and / or displays are not working, but in fact you can have perfectly working displays and cables - but if one cable is faulty it can interfere with the others and make them look bad even if they are not !!

So - I changed all ribbon cables from the display board to the 4 + 1 displays AND NOW IT WORKS WITHOUT ANY FLAWS

Thanks to everyone helping out !!!

Hope someone else will read this a take note of how sensitive the ribbon cables are. That being ALL the ribbon cables - from CPU board to display board and from the display board to the various displays !

#28 7 years ago

ARS

thedefog

Pinside member

That's great news, good to know the LS version works in this case. They don't always seem to be plug and play compatible. Even logic from different manufacturers can cause weird issues, although rare.

1 month later

#29 7 years ago

DBD

doghouse

Pinside+ Addict

15y 98,575 580 15 8

My board guy is having similar problems with my Pinbot board. Anyone know where he can get these replacement SIP's? (CRL8626L CK1. They are 4.7K 470 PF 10 pin). Thanks in advance for your help!

#30 7 years ago

DAV

wayout440

Pinside member

http://www.mouser.com/ProductDetail/Bourns/4610X-101-472LF/?qs=%2fha2pyFadujJBOVebmyFKxUey1DY7Ajd3PuI7ec7SY7Doer8KtZNwg%3d%3d

Quoted from doghouse:
My board guy is having similar problems with my Pinbot board. Anyone know where he can get these replacement SIP's? (CRL8626L CK1. They are 4.7K 470 PF 10 pin). Thanks in advance for your help!

Replace with a 4.7k ohm x 9 resistor bussed (10 pins) with no capacitors. Cut off pin 10 (important!), and install pin 1 (common) in pin 1 of the board. The cut pin 10 of the resistor network does not go into the board's pin 10 position. See notes below for more info on this. Mouser part# 4610X-101-472LF.

#31 7 years ago

DAV

wayout440

Pinside member

http://www.mouser.com/ProductDetail/Bourns/4610X-101-472LF/?qs=%2fha2pyFadujJBOVebmyFKxUey1DY7Ajd3PuI7ec7SY7Doer8KtZNwg%3d%3d

Quoted from doghouse:
My board guy is having similar problems with my Pinbot board. Anyone know where he can get these replacement SIP's? (CRL8626L CK1. They are 4.7K 470 PF 10 pin). Thanks in advance for your help!

#32 7 years ago

HKA

mcklit

Inactive member

Or - if you don't want to cut pin 10 - you can use this one:
http://www.mouser.dk/Search/ProductDetail.aspx?R=4609X-101-472LFvirtualkey65210000virtualkey652-4609X-1LF-4.7K

That is 9 pin with 8 resistors. Install as pointed out in reply from wayout440

1 year later

#33 6 years ago

CDH

chaskett

CHRiS HASKETT designs

9y 44,300 301 2

OP
Quoted from mcklit:
The machine will boot. The 5v+ and blanking LEDs are on and the diagnostic LED is flashing. When booting it starts by sounding 5 beeps - which I believe is a sound board issue and then it will play the "famous" dong letting you know the system is up running.

I just got a pinbot with player 1,2,&4 displays out. Other than this, it was playing fine. I tried swapping all cable, turned the machine back on and all displays were out, made the sound described above, and wouldn't allow me to start a game. I am a newbie to SS games and cannot find anything in the manual describing this sound. Anyone know what means? I was able to get player 3 and credit displays to come back on and the machine to boot into attract mode, but i get the 5 beeps when i hit start, ball ejects, no flipper power. I am at a loss.

#34 6 years ago

DAV

wayout440

Pinside member

Quoted from chaskett:
I just got a pinbot with player 1,2,&4 displays out. Other than this, it was playing fine. I tried swapping all cable, turned the machine back on and all displays were out, made the sound described above, and wouldn't allow me to start a game. I am a newbie to SS games and cannot find anything in the manual describing this sound. Anyone know what means? I was able to get player 3 and credit displays to come back on and the machine to boot into attract mode, but i get the 5 beeps when i hit start, ball ejects, no flipper power. I am at a loss.

Hmmm. I found this that describes 5 tones as a U22 ROM chip error. If it boots to attract mode, that would seem to indicate that the CPU is running. Can you try the sound diagnostic switch as shown below? No flippers could be no power - or it could be no ground (CPU not turning on the flipper enable relay) To determine which, you'll need to measure for DC power with a DMM/Voltmeter at the flipper coil tabs.

Displays could be another problem. If they've never worked since you aquired the game, but one does - they might all be getting display voltage, and it's very likely that they are outgassed, either that or the pins could have cracked solder joints - that's common as well. If you swap the displays around and the working display #3 continues to work in another player position, you have displays that need repaired (or replaced) If I find more than 2 displays need replaced, you end up getting above $100 in gas displays, so I would go to a digital replacement set like Pinscore, then you can eliminate the need for the high voltage section of the power supply altogether.

CPU Sound Diagnostic Switch SW1.
On the left side of the CPU board there are two switches. The top switch SW1 is the sound diagnostic switch. If you press this button, you should get two test sounds. This shows that the CVSD (Continuously Variable Slope Delta) modulator, which produces the game's voices, and the DAC (Digital to Analog Converter) sound circuits are working.

After pressing CPU switch SW1 you should get some tones. Here is the breakdown:

No Sound: sound/speech board is not operating, or a failure is affecting the sound circuitry (broken or disconnected cable, dead amplifier, bad speaker).
One Tone: U23 RAM chip error.
Two Tones: U21 ROM chip error.
Three Tones: U22 ROM chip error.
Four Tones: U21 ROM chip error.
Five Tones: U22 ROM chip error.

The information you need is beyond what is contained in the manual, here's some important links:
http://techniek.flipperwinkel.nl/wms11/index1.html
http://techniek.flipperwinkel.nl/wms11/index2.htm
http://techniek.flipperwinkel.nl/wms11/index3.htm
http://pinwiki.com/wiki/index.php?title=Williams_System_9_-_11

#35 6 years ago

CDH

chaskett

CHRiS HASKETT designs

9y 44,300 301 2

wayout440 Well I've solved one problem... I can now fire up a game. I neglected to mention that when I was fiddling with the displays, I removed the AA batteries on the CPU to check for corrosion, which evidently resets to factory settings making a pay (not free) game. I moved my one working display 3 to display 4 position so I could see the adjustment settings (which worked so I can deduce I have 2 working numeric display cables!). Went to adjustment 23, free play says "No", set to "Yes". Wallah! I can fire up a game again!

The diagnostics CPU LED is flashing and when I press the CPU switch it blinks several times and the blanking led blinks too. I'll have to dig into that next, once I receive my new pinscore LED displays so I can see what the hell is going on. Working on this game with no Williams knowledge and several displays out gives new meaning to Pin*Bot's "Now I see you"

#36 6 years ago

DAV

wayout440

Pinside member