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Video Game Repair/Namco 20 Year Reunion Errors


GalaPac Error
GalaPac Error  
QUESTION: I purchased a used Namco 20 Year Reunion Ms Pac-Man Galaga arcade machine (with operable coin slots). It's in beautiful, original condition, but we have a couple of small problems.

I am new to vintage arcade games, so in no way an expert.  I've built PC's in the past, but that is the extent of of technical abilities (ie, dumb it down for me!).

First problem.  When powered on, I get the following:  Errors Exist. Stuck Switch. Also plays the Pac-Man dying sound.

The joystick would stop going left after some playing time, so I thought perhaps the two problems were related.  I purchased a Haap joystick at a vintage arcade show in Atlanta.  It was simple to replace, and seems to have fixed the joystick problem, but still getting the errors at power up.  Possibly one of the five buttons malfunctioning (althought all works well)?

Second, scarier problem.  After some time, the whole unit will freeze or reboot.  Sometimes accompanied with a Galaga crashing sound.  I figure no good can come of that.

I certainly appreciate any help, and am quite thankful to find this forum!

Thanks so much,


ANSWER: Hi Todd,

Luckily, this particular game is very helpful when it comes to pointing out what is wrong! The "stuck switch" error can relate to any switch on the game, so since you can eliminate the joystick, you need to check the functionality of the remainder of the buttons.

First, put the game into service mode using the service button inside of the coin door. Once there, you can check each switch individually (and it may even say which one is's been a while since i've been hands-on with one of these) Regardless, the switches to check are:

All of the buttons on the control panel
Left and right coin switches
Service switch
Service coin switch

One of those is what is causing your issue. Find it, fix it, and you're good.

The other problem isn't a big deal either- you're likely running at the low end of the voltage spectrum, so I would suggest adjusting up the power supply by turning the voltage adjust knob about 1/3 of a turn. This should keep your game happy and up and running!

Hope this helps,

---------- FOLLOW-UP ----------


Thank you so much for your help and fast response!

Playing with the Test Menu right now.
As you said, I just pressed the "test" button inside the coin door.
That brings up the "Test Menu."
I scroll down to the "Switch Tests" and hit fire, which brings up the "Switch Test" screen.

A checked all the buttons and joystick, and all is well.  All options (left, right, up, down, etc) are white until you activate the switch, and they turn red.  They return to white when you release.

Coin 1 and Coin 2 are already red, which may or may not be correct.
When I drop a quarter in slot 1, it flashes white, returns to red, and makes the normal credit sound.

Slot 2 causes problems!  When I drop in a quarter, it buzzes, freezes, reboots and gives the intial "stuck switch" message.  We've found the problem!!! Slot 2!

Any guidance or videos you'd recommend to fix it?  Is it worth removing and just giving it a good looking over, or best just to order another?  Lastly, where is the best place to order genuine parts?

I'll play with the voltage next, but so thankful for your help in finding my stuck switch!  It was easy, but needed the guidance!


Perfect! This is a very easy fix. It sounds like the coin switches are wired incorrectly- that is to say they are wired to be normally closed, when they should be normally open. There are going to be two wires connected to each coin switch. One will be a ground, and should be on the "long" end of the switch itself. Leave that wire on there. On the "short" end, you'll see a wire connected to a lug, and then one lug with nothing on it. Disconnect the wire and plug it into the other lug. This will now set the switch to "normally open" which is the correct way. Do that for both.

Turn the game on and you should be good to go!

Let me know if this worked out!

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Brian Penzone


I can answer questions regarding coin-operated arcade game questions down to the logic board. Error codes, erratic operation, dead boards, I can help with them all. I can help with video monitors on a very limited and basic level only.


I have spent nearly 20 years as an avid arcade collector, and spent nearly 10 of those years as the lead tech for a large arcade operator, doing work for manufacturers and other coin-operated amusement companies around the globe. I maintain a good sized collection of arcade games, as well as a large inventory of spare parts for a wide range of arcade machines.

BA from The Ohio State University, Associates from DeVry University

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