Ms. Pacman Cocktail Issues - Garbled screen, controls, sound, and lighting issues

timlah79

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Donor 2018, 2023
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Hi all,
I'm trying to help a friend figure out what's going on with his OG Ms. Pacman cocktail cabinet. It has suffered some moisture damage. It was working 100% probably a year ago but then it was placed in an outdoor shed. :( While it looks terrible because of that, I feel like electronically it can be fixed with not too much effort. If it can, then I will help him restore it aesthetically. If it isn't going to be an easy task, I'll probably convince him to part it out and sell it. Anyway at this point I'd just like to get it playing again. Disclaimer: I know little to nothing about fixing cocktail cabinets. I have done what I can to troubleshoot and try to learn given the original manual: https://www.arcade-museum.com/manuals-videogames/M/ms_pacman_p1.pdf

The good:
1. It appears to "mostly" boot up. Meaning the fans come on and an image is shown on the original CRT.
2. The coin door maintenance switch and button seem to do something.
3. The red switch on the board when pressed does make some difference on the screen.
4. None of the lower fuses or the CRT board fuse appear to be blown.

The bad:
1. The screen image is just a garbled mess. Can't tell what's going on i.e. if the game is in test mode or gameplay mode or anything.
2. Both sides' controls / buttons seem to do nothing.
3. There is no game sound at all from the speaker but I hear something kind of "glitch" from the speaker.
4. Nothing else lights up. None of the marquee lights, the coin door lights or anything.
5. When manually trying to add credits, I'm unsure if anything is registering since I can't really see what's going on on screen and there's no sound to indicate.

Troubleshooting:
1. While running, I hear the faintest beep, pause, beep, pause I think coming from the motherboard.
2. Wiring: Visually inspected everything. All molex / wiring seem to be connected.
3. Fuses: Look fine. I have not tried to replace them yet or do any MM testing.
4. Transformers: They clearly look rusty.
5. MB: Everything seems to be seated properly.
6. Yellow ground cables: All appear to be secured except for one end of one that isn't attached to anything and another that looks as if it has been cut. For all I know, these have been this way even when the game was working.
7. Testing with the coin switch. Something changes when I flip the black switch L/R and when I push the red button but I can't tell what is happening. That at least means that mechanism is being recognized in some way by the MB.
8. The red switch on the motherboard: Holding that in shows a ghost on the screen, letting it go goes back to the garbled animation.
9. This might be my first indication of what to fix: I can sometimes get the screen to show "BAD" (something). It looks like its trying to show BAD CRM. I see in the manual a table referencing "BAD" codes but I can barely make out what its telling me and what exactly I'm seeing doesn't align with the manual or I'm just not seeing what the test mode is trying to tell me b/c the screen is garbled.

See various images attached. I have videos too I just can't upload them in the forum. And I have a lot more photos just LMK what else you'd like to see. Sorry they are terrible and glared. Very difficult to get good captures. I really appreciate any advice!
 

Attachments

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  • Ms Pacman - Top View - Screen On_50.jpg
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  • Ms Pacman - Yellow Ground Wire.jpg
    Ms Pacman - Yellow Ground Wire.jpg
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Last edited:
If this game was exposed to moisture, then anything metal inside could (and probably does) have corrosion.

Start at power. Original fuse blocks on Pac games are garbage and should be replaced, long term. In the short term, clean them. Keep track of where each fuse goes.

Clean the fingers on the game pcb. Fiberglass pen or rotary tool with a brass wheel. Then wipe with DeOxit.

After all that, check to see if you are getting 5VDC at the board.
 
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