START HERE! Step One: Getting Started
Welcome To FixYourPacman.com. The sole purpose of this site is so that a Pacman or Ms Pac-man owner like yourself with little or no knowledge of the inner workings of an arcade machine, can quickly diagnose and easily fix your Original Pacman coin op game in the absence of a qualified technician; which quite frankly are a dying breed these days. So please follow the directions step by step in order to completely trouble shoot your problem so we can have you up and running in no time.
IF YOU HAVE AN 80’s ARCADE GAME OTHER THAN PACMAN THAT NEEDS FIXING CLICK HERE!
IF You Have a Galaga Machine Click Here For FixAGalaga.Com
Safety First! —Your Safety is important. Always UNPLUG your machine while you are working on it. If the instructions call for you to plug the game back in to test it, then please don’t touch any of the electrical parts inside– basically please use common sense and use your eyes instead of your hands while the game is plugged in or turned On.
Note: These instructions are intended to diagnose only the problems of an original coin-op Pacman or Ms Pacman stand up and/or an original Pacman or Ms Pac Cocktail Table Machine or Original Mini. All other Pacman variations or newer MAME type games, multicades, or other computer games are not meant to be diagnosed through this site. I’m also assuming of course that the entire Pacman or Ms Pacman game is complete and has the original PCBs, monitor, power supply…etc; which is all hooked up right and was working at one time, but now it is not.
Note: You may think you already know what the problem with your Pacman is, for example you may think you have a bad monitor; when in fact it could really just be a simple blown fuse or a power supply problem or you may even perceive you have a Printed Circuit Board (PCB) issue, but what you could actually have is a wiring problem or an Eprom issue etc. So again please follow these steps as directed to correctly diagnose the problems and don’t assume it’s one thing or the other until each has been ruled out or you’re ask to move on to the next step. I have purposely written each post in an easy to follow hopefully non-technical way so that even a novice can understand. So follow each step and we’ll get you to the root of the problem as fast as we can. In many cases the following steps can be used to diagnose or repair other arcade games of the era, so if you have other arcade game models besides Pacman then in many cases the problems will be common to all. Basically an arcade machine consists of a power supply, monitor, a PCB, and controls. So you may be able to diagnose your problems through this site for a similar type game, but Pacman or Ms. Pacman will be the sole focus moving forward. Please read our disclaimer in the footer below before beginning. With All that being said, let’s jump right into it! Take a moment to review the picture below to get familiar with your Pacman Machine.
Then Please Proceed to the Step Two Post: Blank Screen Repair.
If you have a Cocktail table game then proceed to the Pacman Cocktail Table Repair Post First.
Proceed To Step Two
Looking for hard to find Pac/Ms Pac parts for your game? Click here for our Parts for Repair Page
My Ms. Pacman screen blinks the word bad in top left corner and near bottom its blinking icons
I’ve never had that type of problem yet…but it sounds like bad chips or roms…Are you using an original pacman board or a jamma board type clone? If you are using an original take your board out and re-seat all chips (eproms) as labeled on the pac pcb page (6e -5f plus 4A and 7f) Make sure all the pins from the eproms or proms are re-seated one in each seat and not bent underneath or out of socket….My guess is that you have a dirty contact or a pin problem, but a lot of times that will cause scrambling on screen and not a word like “Bad” to appear which suggest something else…I’m so sorry I have never experienced that….You may also have a clone board installed which I am completely unfamiliar with.
Simply unplug the game …then bypass the on/off switch at the top of the game by wiring together the two wires connecting to the on/off button switch to always stay on. Simply cut the two wires where they connect to the power button at the top of the game then expose the ends…. then twist the two ends of the wires together connecting them. use Electrical tape or a cap to the joined ends of the two wires.. Then take your plug and plug it back in to turn the game on or unplug for off. Just bypass that button
my ms pac flashes number 1 in top rt and shows one garbled character.
I disconnected daughter board and set z80 on main. same outcome…
i hv read elsewhere this is likely bad 2114 chip at 4R. How do I verify. no access to working board or known good replacement chip…
Help is much appreciated!
Armand in Canada
First rule out the simple…Like is the v-ram board properly seated with all the pins seated and not broken or out of socket. Next make sure the vram is oriented the right way (if tie wire still in it make sure its not shifted..if already cut take it out and clean pins and re-seat again). Also do this for everything attached to the pcb and/or eproms etc…I find that usually eliminates about 60 percent of the problems. If this doesn’t work then it might be easier to just start replacing parts until the pcb works again unless you can find a replacement 4R etc..but I bet ebay would have the whole board or vram for just as cheap as you could replace one chip.
Also pay close attn to ROM at 6J at the board. replace this rom.
Replace the 2114 ram with this
http://www.ebay.com/bhp/2114-ram
I should have mentioned – this machine had been working fine for years and is not a new acquisition. One day when turned on it produced the flashing number 1 in top rt and shows one garbled character. I checked the standard things (chips properly seated etc.). I am completely new to PCB diagnostics etc and don’t have anything to properly test the ram/roms for proper operation and I am not in a location with any solid game PCB repair shops. Working boards are pretty expensive on Ebay so I am a little hesitant to try that option. I notice the edge connector looks pretty bad on this unit and appears to have been mucked about with at some point in the past. I assume if voltage is wrong coming off any of the edge pins, whatever is downstream will be fubared. So maybe I should start with there? Can the behavior described come from a variety of causes? I don’t see too many reports of this specific problem online… Help is much appreciated.
I also forgot to ask – about testmode. Machine will not enter test mode so I assume the issue is upstream of the components required for testmode to execute? There is a kit available online from http://twobits.com/ABC/ – does anyone have any experience with this diagnostic kit and is it something that is likely to help with the problem described?
Cheers!
Yes I have had good luck with this kit..also with the super abc kit by two bit…u can check the continuity of the edge connector by putting one end of the probe just below where the pin connects to the edge connector….then the other end to the other part u want to check or above the edge connector….with the power off…if u have a beep then the electric is able to go through the connector if not uve found that the edge connector is not properly working
I need help with a Ms Pac Man/Pac Man/Galaga machine. I cannot get the power button unstuck from the off position to the on position. Any help would be greatly appreciated.
Is there a way to make the machine hold the high score after shutting the machine off with either the power button or after power loss? I have a Ms. Pac man I am sure it needs some battery replaced some wher on the pcb but I don’t have a lot of is knowledge in this arena. Love the site, glad I found it, already solved my sound issue I was having.
Glad to hear your sound problem is fixed!!! Two Bit Score super ABC Kit saves the high scores plus lets you continue where you last died. Other than that seems like Mikes Arcade site used to advertise a pac high score save kit as well…I’m afraid you may just have to search youtube or google to see if anyone’s added a battery or hacked into the game in order to save the score…Sorry never have tried that other than I have installed many Multi pac kits, both Clay Cowgill’s multipac and Two Bit scores super abc kit.
Thanks for the info. Just assumed that the high score would remain if power loss. I assumed that like a computer board the pcb would just have a battery on it to hold memory and the 30 year old battery was just shot. Oh well. All others are working, even changed out the ballast on the upper panel to make the front light up. Thanks again for the site and look forward to future post and updates.
I have a ms pacman mini standup game. I cannot adjust the horizontal view of the monitor. So, you cannot see the complete top(your scores) or the complete bottom. I’ve checked the b plus voltage is correct. The H size pot ohms out, but not sure what the value should be? Any suggestions/help is appreciated!
My pacman machine has been unplugged for a few years I plugged it back in and it is not coming up i. English??
Should be very simple…either the interlock switch on the back door or a fuse blown ..please start at step one or two of this website and it will guide u through
I have a pacman jr. game that I inherited. The game seems to be stuck in attach/demo mode. I cannot play the game. I’m sure there’s a simple fix but know nothing about this game system. Any ideas how to make the game available to okay?
So if I’m reading this correct. The game does not start up when u put a coin in right? You’re saying it stays in attract mode or demo and nothing will start it? If so open the coin door with power on and with your finger press the lever down at the bottom where the coin falls through on the coin switch. (This can be explained if you go to coin slots page on this website for pics, steps etc) If you cannot manually coin the game then look for broken loose wires going to the coin switch, i’ll bet one of the wires are loose or fallen off the coin switch. Or you may have to just order a new coin switch. Try both switches on the coin slot. there should be two side by side.
That did the trick. Thanks so much!
Great site! Just inherited 1981 ms pacman. Everything works great, screen is jittery. Any ideas?
Thank you!
Michael
Yes try adjusting the pots on the neck or chasis board of the monitor itself..consult the manual for them ..see if you can adjust it first….if no luck there consider getting a cap kit for your monitor…. read the cap kit page on our website for more instruction
Recently my Ms Pacman stopped booting up. I would get a screen full of letters and numbers. After troubleshooting, I get it to boot up but only when not in Free Play mode. There are no coin slots, so I can’t fully test out the controls. Have you heard of problems with Free Play mode?
I’d try to re-seat all the eproms..clean each pin with a pencil eraser and then carefully reseat each eprom as mentioned on the eprom page..sounds like a bad connection also try this link to see if a pic of ur problem is in there https://www.mikesarcade.com/arcade/pactrouble.html
Thanks for the fast reply!
I don’t see a screen similar to the one I get…. see mine here…. http://scubadive4fun.com/public/IMG_3988.JPG
Plus, I also purchased a working Ms Pacman PCB, thinking mine was dead. And with very little experience troubleshooting PCB boards, thought this would fix the problem! None-the-less, the same problem occurs. Yet nothing has been touch internally with wires or connections. Puzzled!!!
Ok if a new board didn’t help then u can rule out the pcb..unless u used the same vram or daughter board..if so check to make sure a pin hasn’t been folded up underneath on the vram to the pcb or daughter card…or start replacing boards : u said u already bought a new pcb did it come with all boards installed…in other words..think in terms of status: what have I replaced new and why is it still doing the same thing..what is left on from the old. Since ur screen is scrambled that is what’s coming to the monitor from the pcb daughter cards and eproms etc..so more than likely without being able to see ur game I’d say the problem is board or vram related….u might want to check everything going to ur monitor from ur boards including ur pcb connector..id replace the old connector with a pac to jamma connector and a new 15amp power supply too..in case there’s a bad connection or a short somewhere there…replace until working that’s all I know to do…when u check it look for shorts..bad or burnt places or pins bent dirty or broken
Than
The PCB purchased was complete…. had all daughter cards, so nothing was used from my original board. I just purchased a new power supply, pac to jamma board and harness. I will rewire everything. Might be a longer route but at least it will resolve the problem…. in theory! Thanks again!
Well…. totally baffled at the moment.
New power supply
New CGA to VGA video card
New Ms Pacman to Jamma adaptor
New Jamma Harness
I hooked up just the power and video wires, and I get the same problem…. nothing but random color numbers and characters on the screen at boot time.
Game should still boot without controls hooked up right?
Never would have thought that the DIP switches would have this impact. But after changing some of the settings on the new PCB, and going back to the desired game settings, it booted up! Game is back up and running. I have not tried the original board, as right now, way too much time invested. What a learning experience.
Wow That’s a new one on me..Congrats
Coin lights used to work, now don’t work at all even with new bulbs. Everything else is fine. Is it just a fuse issue like I suspect?
Yes this should be a simple fix…Sense u have new bulbs… then with a multimeter go back and trace from the socket to the power supply looking for breaks in solder joints and also breaks in the wires that lead to and from the sockets etc…until you find the voltage break. Most likely something real simple like a break in continuity or a wire fallen off unsoldered. also Check all fuses if you can’t find where the power breaks go all the way from socket to beginning of where power for the lights start.
Hi there. I have an original ms PAC man coin operated.
I get a screen with numbers and letters. Do you have any suggestions. Thank you.
Yes go to this page http://www.fixyourpacman.com/trouble-shoot-by-pictures-whats-on-my-screen/ and scroll down until u find what looks like what ur screen is showing u…the solution is underneath the pic
I have a replica of the old style PAC Mac gaming table. We recently moved and it has an error message stating the monitor works but it will not boot up to play. Any suggestions? We have looked at the wiring but don’t see anything unplugged.
Several things you can check…First with the game unplugged, open the game and find the 44 pin harness connecting to the top of the pcb board; unplug that and then plug it back in..This makes sure there is a connection of power getting to the board as it may have been jarred around in the move…if that doesn’t work try to make sure the interlock switches are all working and pulled out all the way or pressed all the way in…sometimes when you move these get jarred and turn off the game..I explain interlock switches I think in step 2 on this site. If none of those things work make sure you have a working 15amp power supply
I have a standup Ms Pacman that generally works fine. I noticed (in moving the game) that depending on the direction the game is facing..that there is a loud hum. If i rotate the game 90 degrees.. the hum goes away. thoughts?
If a Hum is heard during Sound its in Rams @ 2L & 2K theyre bad
If Clicky Sound
Replace 74LS174 @ 1L
Buzz in music & after game over but not before start of game upon initial power up or reset.
Replace 4066 @ 1N.
Distorted Intro Music – Other Sounds okay – Seems thermal/Cap like
Replace 74LS174 @ 1L bad on Pin 14. Bug trap only shows when starting game.
Muffled Sounds, seems like intro music is Slow.
Pin 10 @ 2L (RAM 7489/82S25) out of circuit.
Intermittent loss of Sound (Static)
Modification
Cut trace to pin 1 of 2M (74LS273).
Solder 1K resistor from +5VDC to pin 1 of IC 2M
I have a Pac-man clone board , Some guy tried to fix it and he messed it up further. he cut off a few IC’s and I have no idea which one were originally there . The board only says “GP” on it . no other identification. The chips locations are marked eg IC 42 so i cant figure out its corresponding IC on the original PacMan schematics.The screen is full of multi colored squares and mini ghost characters, so i’m guessing its a logic problem. Please can you help I really need to fix it .
So sorry I’m afraid I know nothing of the chips ICs roms etc that make up a clone board..might want to goto eBay and buy an original midway Pac board..theres links on my sight under Pac man pcb repair
Thanks , I might have to go that route , i can see the Z80 cpu on it and other chips mentioned on your site but finding those missing chips on the pcb is a nightmare. Thanks for all the info on yr website
I have a miss Pac man that just shows a blue screen and nothing else no sound
3A bad or missing.or
3A Pin 9 short to pin 13. Check for further help the page “what’s on my screen” and scroll thru til u find what looks like ur problem
Line in middle top to bottom
No sound
Looks like original power supply
U have a vertical collapse
Try this
https://youtu.be/Em6gOuBpLWU
Got a Ms. Pacman arcade game last night. The artwork looks great only cosmetic things it needs is the bezel as the one side has come away from glass. When turning the power on the marquee lights right up the sound and picture also come right on. I can play the first wave but once cleared the screen goes dark and only the number 1 flashes. Any clue what I need to fix this and is it hard to do? Thanks
4R ram on the video board is bad..located 4r from the pcb board or manual on the site..try to resolder all pins and make sure nothing is shorted on it
Thank you. If unable to repair what is the exact part that i would need. Also do you know where I could buy a good quality bezel? Thanks again.
Good monitor bezel here: https://www.ebay.com/itm/BRAND-NEW-MS-PAC-MAN-Arcade-Machine-BEZEL-Screen-Print-High-Impact-Plexi/302594899115?hash=item46740fbcab:g:AH0AAOSweXhXmVKi
Hello,
I have an arcade machine that has been working great until recently it started distorting images on the screen. However after looking through your archive of diagnoses, I haven’t been able to quite match up what I am seeing on my screen. Would it be possible to email you the images?
Thank you!
Yes Stuttle1970@att.net
My PacMan is working fine, I just want to replace the monitor with a new LCD one is there a quick kit for this that you would recommend? Thanks
Yes there is click here https://rover.ebay.com/rover/1/711-53200-19255-0/1?icep_id=114&ipn=icep&toolid=20004&campid=5337835944&mpre=https%3A%2F%2Fwww.ebay.com%2Fitm%2FVideo-Converter-Board-CGA-EGA-YUV-RGB-TO-VGA-Arcade-Game-Monitor-to-LCD%2F253405588134%3Fhash%3Ditem3b00266aa6%3Ag%3ADikAAOSwZfNadORE
Hi, I just came across a Jr Pac-man that was sitting in this guy’s garage. He said that it worked when he put it in there, but now, the screen will light up, but nothing else. It’s just a static screen like the old school tv’s without an antenna attached. He said that he had the main board replaced, and there is some sort of tag on it. The board looks like an original Jr Pac, “JR PAC MAN” is printed right on the green board. After reading some of the posts in here, I think that I will try to wiggle a few wires, and check fuses and see if that works. Also, the screen is pretty burned in, so I was thinking about converting to LCD, I ‘ll have to look and see if I have one laying around that is the same size. I have heard that the Jr Pac’s are hard to keep running, are there any notorious problems with this machine that I might want to check out? The case on this thing is pretty messed up, they painted it yellow, and did a pretty crappy job of it. I’m a cabinetmaker by trade, so I don’t mind repairing or rebuilding the cabinet, but I want to make sure that the machine is going to work before I go through all that. I downloaded a user’s manual for this game, but it doesn’t have a troubleshooting section. Any help that you can give would be greatly appreciated. I’m hoping that this thing doesn’t cost a fortune to fix. I only paid 60 dollars for the machine, so if it’s too far gone, I’m not out too much, unless some of the parts might be worth something.
I have a stand up Mr. Pacman and the entire screen is scrolling from right to left and when about half of the screen is scrolled it reset a then does the same scrolling loop over and over
I’m sure u have tried to adjust the screen from the knobs on the monitor but if u haven’t first try adjusting the horizontal hold knob…also please goto the trouble shoot what’s on my screen page in the menu of this site and find the pic that looks most like what’s happening on ur screen
Thank you for the reply. So I left the game on and every 30 seconds or so the scrolling slowed down until it finally stopped. It was almost half cut off and then it started to slowly scroll back from left to right this time until it centered out and stayed there. Fully functional and no pictures cut out or distorted it’s just a scrolling screen.
Where can I find these adjustment knobs?
Thanks again!
https://youtu.be/MUL5TiUYAss
Here’s a vid to explain it
Hello, I completed a monitor swap(LCD) for an original MS PAC MAN and all worked well for 2 days. Now cannot get the monitor to power up – marque and lights work fine. Is there a way to check for power or connect directly to monitor to troubleshoot?
All original except for monitor. Thanks.
Do you hear the sounds of the game? In other words everything is working except no power to monitor to show whats on screen? If so make sure that the power chord from the monitor is hooked it to the power coming from the power supply or the game cabinet. I really don’t know how the LCD monitor power source works but somewhere in the game it should be connected to a 110v source. (since it was working and not not then Im sure its something simple ) Also I would check the fuses to the monitor. If no sounds of play from the board when you coin the game and press start, then try the interlock switch located on the back of the game, make sure to pull it in the out position or in position if the back of the game is keeping it pushed it…more on this on my blank screen post
Hello, I have an original Ms Pacman upright machine that is well loved but not altered or changed. The games boots up fine, runs demo awaiting a player, accepts and registers quarters however the player 1 and player 2 buttons are unresponsive to start playing. When I open the panel, I can see the buttons pushing the metal contacts together however nothing starts. Any ideas?
Yes when u open the panel..first look for a loose solder joint or loose wire if u find that solder it back on…if all wires seem or look connected then you at the end of the leaf switch and with a piece of sand paper place it between the switch contacts and clean any dirt or grime..might be as simple a dirty contact
I have a ms pacman that works great. But I can’t read the score at the top of the screen. Any suggestions.
Steve
yes goto the back of the monitor and find the knob that will shrink the screen down. THis will more than likely reveal the score. In other words the knobs on the neck and chassis of the monitor. Goto my monitor pages to see where they are. Once adjusted down the height of the screen will be so that you can now see the score
I TRIED YOUR SUGGESTION. IT APPEARS THAT THE WHOLE SCREEN IS BIGGER. IF I PULL DOWN THE TOP, I LOSE THE BOTTOM. IF I ADJUST THE SIDES, I I LOSE ONE SIDE OR THE OTHER. WHAT NEXT.
STEVE
Ok what is the make model of your monitor? I will need to know that first
the Type # A48KRD89X
the Serial #M5450400455
TYPE #A48KRD89X
SERIAL#M5450400455
Need the name of the monitor..it needs to be a 19″ ctr horizontal monitor like an electrohome g07 or wells Gardner k4700 or 7000 etc need the name of the monitor or take a pic and send it to me..i do not know how a new flat screen etc works with a original Pac pcb..so if it is a mame game or a flat screen..i won’t know how to fix
Stuttle1970@att.net
HOW DO I SEND YOU THER PICTURTES?
To stuttle1970@att.net