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(Topic ID: 156364)

Congo dead - help please

By jawjaw

4 years ago

Topic Stats

  • 20 posts
  • 9 Pinsiders participating
  • Latest reply 4 years ago by jawjaw
  • No one calls this topic a favorite


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#1 4 years ago

I can't catch a break with my Congo. One issue after another since day one. I was playing it for around 30 minutes last night, everything was fine, and it just went dead in the middle of the game. No lights, no dmd, no sound, nothing. Only thing that works is a volcano led strip mod. It connects to an unused PLFD connector on the driver board that seems to get constant power. Leds on the boards work so appears boards are getting power. Fuses all check good using multimeter. On bootup, the bottom cpu led (202) is always on. The top (201) comes on during cold bootup, fades, and then barely on with a flicker. The cpu gets pretty hot very quickly but not sure if that is normal. Last night after running for 30 minutes, the top 201 led never came on after power cycle. The middle 203 led is always off - never blinks. No bongs on bootup - only a slight normal buzz sound. Does same thing if I disconnect all cables on the cpu board except power.

Before this issue, I was having switch matrix short problems. One column was out that controlled lower playfield CONGO target switches and AMY switches. Hitting one of those switches got a row short. Replacing the U20 chip fixed that but it happened again later. Only thing I did was pull the playfield out and rest it on the rails (power was off). I threw in another U20 chip and it was working fine for several days. Perhaps related to current issue.

The cpu board was treated for some minor battery corrosion last Fall but someone local. It was working fine at the time but wanted to make sure it was not an issue later. I don't think anything was replaced - just neutralized, cleaned up, and battery holder replaced. I've used a remote battery holder since I got the game so no chance of new corrosion. Some of the solder joints still look a bit suspect, though. Not sure what it looks like when bad and doesn't look as bad as some pics I have seen. I also don't like the looks of the chip marked "BA10339 523 L03" and the D28 thing next to it. Looks like corrosion or something leaking. I suspect the cpu boards need repairs but like to have some idea of what is going on. Any help would be appreciated.




#2 4 years ago

Have you checked voltages coming from the transformer and driver board? Maybe something new has gone wrong.

#3 4 years ago

It doesnt look too good around U5 either...

#4 4 years ago

That board needs to be fully neutralized of corrosion. All those solder points that look 'fuzzy' have corrosion. Corrosion on a trace introduces resistance that shouldn't be there and can turn a HI signal into a LO signal and flip out the logic. If you probe from solder point to solder point (no in-series components) and get more than an ohm or so of resistance that circuit is going to flake out. Just a little corrosion can change traces' resistance and BLEH! It quits working.


#5 4 years ago

send the CPU board to Coin-Op Cauldron

#6 4 years ago
Quoted from swampfire:

Have you checked voltages coming from the transformer and driver board? Maybe something new has gone wrong.

I have a good multimeter but not sure how to do that. Any tips? I have not dealt with these kind of issues before.

Quoted from pinwiz_pa:

It doesnt look too good around U5 either...

Agreed. The components look okay but all the solder looks dull.

#7 4 years ago

Pull the CPU board and take a shot or two of the back, let's see the tracers as well.

#8 4 years ago

Here is the back of the cpu. Looking kind of ugly on the bottom (right side of pic).


#9 4 years ago

Can't be 100% certain but it does look like you might have some tracer issues here.


#10 4 years ago
Quoted from DeathHimself:

Can't be 100% certain but it does look like you might have some tracer issues here.


And that's U23 maybe?

#11 4 years ago

That is the U23. What does the it do? I noticed it was a bit loose but pushing it in didn't change anything. Should I try replacing it or are the problems sounding bigger than that? I replaced the U20 a couple of times which fixed switch matrix grounds but not sure what cause the shorts in the first place. I never work on anything with the power on.

#12 4 years ago

Looks like a board I would replace. Problem is definitely because of the acid damage which migrated to the back side of the board.
If you don't like Rottendog, PinLED also has a replacement.

Original boards in nice working shape are very hard to come by.

#13 4 years ago

I'm not thrilled with replacing it but that may be the best plan. I already have a rottendog av board in it so might as well get a rottendog. Where is a good place to get one? Can I get a bare board and swap over chips? K's Arcade wants me to select my game which adds $95 but not sure why. Any advice?

#14 4 years ago

Yes, you can get a bare board and move your chips over.

#15 4 years ago

I installed a new Rottendog mpu. Game booted up and played okay but dmd was garbled. Swapping the 34pin ribbon cable that goes to the av board helped a lot. Almost perfect but still some extra dots and distortions now and then. The cable I swapped was one I had laying around. It has two other connectors so not exactly designed for wpc95 (for wpc). Is it bad to use this cable? I can get the correct cable but not sure if that is really the problem.


#16 4 years ago

No big deal having some extra connectors not being used. Though, at first you had some garbled display so that still is suggesting you have bad connection on the ribbon cable. You could swap the cabile and/or DMD with Getaway to verify which is still giving you the current issue.

#17 4 years ago

Scratch my last post.

Oh I do believe that the original ribbon cable is wrapped through/around a ferrite. I think this actaually is to reduce the extra dots/distortion you are seeing. I would actually swap back to that cable. If the DMD is garbled again, reseat both sides of the cable.

#18 4 years ago

I did try swapping the dmd cable from my Getaway since it's fairly new. I had similar issues with my Getaway a while back and the new cable fixed that. Didn't help in my congo. I also tried replacing the other ribbon cable that goes to the av board. No change. Only when I change the 34 pin cable did it help.

#19 4 years ago

Man you have had nothing but issues with this pin... and to think i almost got it shipped to me when it was for sale. I really hope u get it figured out .i wld definitely get the correct cable to eliminate thst as the cause. These ribbons can make these wpc pins to crazy stuff.

#20 4 years ago

I gotta admit you dodged a bullit with this one. I should of been more careful but easy to say that now. The good thing is it has taught me a lot and a feel much more comfortable digging into my pins.

The biggest problem was the rottendog av board. Took a long time to determine the exact problem and then took rottendog 3 months to get it back to me repaired . To their credit, they did not charge me a penny so cannot be upset. I'm hoping the new mpu will finally get it reliable. It should definitely help. The old mpu had a lot more corrosion damage than I first thought. Getting a new board was not too expensive so happy about that.

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