Mr. & Mrs. Pac-Man
Bally, 1982I installed leds in my Mr mrs pacman and when I attempted to turn the game on the back display flickers quick then goes off. Half the GI lights on the playfield are not lighting and the game doesn't start, have sound or do anything. I think I may have pinched a wire somewhere because the game work fine a week ago when I turned it on. Would the new leds have anything to do this?
Quoted from CNKay:You likely have a couple issues that popped up at the same time. Start with power supply and work from there. You can't throw LEDs in a bally mpu controlled lights without other work.
What exactly would I have to do? Would a led adapter made for Bally machines do the trick, I saw comet pinball sells them. Or is there more to it then just that?
Quoted from Jasenwm:I attempted to turn the game on the back display flickers quick then goes off. Half the GI lights on the playfield are not lighting and the game doesn't start, have sound or do anything.
Time to look at the LED on the MPU board and see if it flickers and then flashes 7 times for a correct boot up of the game. Sometimes, it is part failure, connection failure, voltage failure. After counting the number of flashes, reseat the top left 2 connectors on the MPU (top left) board and the top right connectors on the solenoid driver (top right) board. If this works, then you have a temporary fix and connectors and board pins would be the first thing to replace.
Quoted from PinballManiac40:Time to look at the LED on the MPU board and see if it flickers and then flashes 7 times for a correct boot up of the game. Sometimes, it is part failure, connection failure, voltage failure. After counting the number of flashes, reseat the top left 2 connectors on the MPU (top left) board and the top right connectors on the solenoid driver (top right) board. If this works, then you have a temporary fix and connectors and board pins would be the first thing to replace.
Thank you so much!
Quoted from PinballManiac40:Time to look at the LED on the MPU board and see if it flickers and then flashes 7 times for a correct boot up of the game. Sometimes, it is part failure, connection failure, voltage failure. After counting the number of flashes, reseat the top left 2 connectors on the MPU (top left) board and the top right connectors on the solenoid driver (top right) board. If this works, then you have a temporary fix and connectors and board pins would be the first thing to replace.
So I removed all the leds and the reseatted the connections. The led on the mpu blinks three times with no change from what it was doing before which was nothing
Oh, there was no need to remove the LEDs. That just happened to be coincidence that it failed post LED install. I'm sorry if you had thought I suggested that.
Quoted from CNKay:You can't throw LEDs in a bally mpu controlled lights without other work.
Only issue you would have been seeing is the LEDs would have been flickering and/or ghosting (staying partially on when it should had been off).
Quoted from PinballManiac40:Oh, there was no need to remove the LEDs. That just happened to be coincidence that it failed post LED install. I'm sorry if you had thought I suggested that.
Only issue you would have been seeing is the LEDs would have been flickering and/or ghosting (staying partially on when it should had been off).
I'm not sure how to troubleshoot this. What in your experience think happened? Would the leds blow a fuse or fry the power supply? Not sure what to do next. I did check the fuses and they seem to be good. I'm just annoyed because all the work I did to this machine and was about done now it's unplayable. I appreciate the info
If you have the flicker then 3 flashes, swap U10 and U11 to see if get 4 flashes. If so, 6821 is needed. This is a good replacement. https://www.mouser.com/ProductDetail/western-design-center-wdc/w65c21n6tpg-14/?qs=opBjA1TV902p0LqHsLVgSw%3D%3D&countrycode=US¤cycode=USD
If you have the flicker then 2 flashes, then you need a 5101 RAM. Best to upgrade to 5101 NVRAM even if this is not the failure. https://www.pinitech.com/products/5101_nvram.php
Quoted from PinballManiac40:If you have the flicker then 3 flashes, swap U10 and U11 to see if get 4 flashes. If so, 6821 is needed. This is a good replacement. https://www.mouser.com/ProductDetail/western-design-center-wdc/w65c21n6tpg-14/?qs=opBjA1TV902p0LqHsLVgSw%3D%3D&countrycode=US¤cycode=USD
If you have the flicker then 2 flashes, then you need a 5101 RAM. Best to upgrade to 5101 NVRAM even if this is not the failure. https://www.pinitech.com/products/5101_nvram.php
I already did the 5101 navram when I bought the machine. I'm going to check out what you said with the other roms
The flicker can be really short and not seen - 2 flashes means the 5101 is suspect then, its socket, or traces around there.
You should start from the beginning, since it's unclear whether or not you're seeing the flicker. The MPU will always start with a flicker if it is starting it's normal booting routine.
Keep your eye on the MPU LED when you flip the power switch. It will flicker. After the flicker, start counting how many flashes it does. There's no point in troubleshooting anything else without an accurate assessment of the MPU flash counts.
If you need to, post a video so we can take a look and determine the number of flashes.
Quoted from barakandl:counting flashes. flicker not visible in this video.
This is a perfect example of what we will need to see to help you get your game up and running.
So I did post a video to youtube but I can't figure out how to get the video on pinside? A update of the current status...I went and replaced the lamp driver board,MPU,Solinoid driver board and the power supply board. Every board but the sound board, now all the sudden the there is no power to MPU. once I replaced all the boards the game was doing the same thing, a few lights on the play field on ,no sound, MPU led blinking three times , game won't boot or do anything. I tried checking the voltages and it appears the power supply board which is new is giving off very low voltage to the other boards. So I'm thinking maybe i's the transformer? I'm at a loss with this at this point
MPU Led flicker on power up then 3 LED flashes means the game has detected an issue with the 6821 PIA chip at U10.
Now you've already changed U10 so the issue is probably not the chip itself.
A test failure of the U10 chip on power-up can occur if there is a short circuit external to the chip.
U10 controls all the game switches, lamps and sections of the displays.
Your next step is to isolate all these components to narrow down where your short circuit is.
So with the power off, disconnect the J2 connector, J3 connector, and J1 connector off the MPU board and power up. This is the playfield switch harness, cabinet switch harness, and lamp/display control harness respectively.
Power the game on and see if you get the MPU LED flicker then 7 LED flashes.
If you do, power off, and reinstall one of those connectors at a time until you find which connector causes the MPU LED to flash only 3 times.
My money is on one of the LEDs you installed on the playfield has shorted to one of the playfield switches.
Quoted from Quench:MPU Led flicker on power up then 3 LED flashes means the game has detected an issue with the 6821 PIA chip at U10.
Now you've already changed U10 so the issue is probably not the chip itself.
A test failure of the U10 chip on power-up can occur if there is a short circuit external to the chip.
U10 controls all the game switches, lamps and sections of the displays.
Your next step is to isolate all these components to narrow down where your short circuit is.
So with the power off, disconnect the J2 connector, J3 connector, and J1 connector off the MPU board and power up. This is the playfield switch harness, cabinet switch harness, and lamp/display control harness respectively.
Power the game on and see if you get the MPU LED flicker then 7 LED flashes.
If you do, power off, and reinstall one of those connectors at a time until you find which connector causes the MPU LED to flash only 3 times.
My money is on one of the LEDs you installed on the playfield has shorted to one of the playfield switches.
Thank you I'm going to try that and report back
Quoted from Quench:My money is on one of the LEDs you installed on the playfield has shorted to one of the playfield switches.
This is 100% correct, was a GI socket pressing down on the left gate switch leaf.
Quoted from gdonovan:This is 100% correct, was a GI socket pressing down on the left gate switch leaf.
Thanks for the update.
You've taken ownership of this game now yes?
Quoted from Quench:Thanks for the update.
You've taken ownership of this game now yes?
Yes. Though it might go to Colson in the future, see update in my Flash Gordon thread.
Isolating the MPU allowed it to boot up completely and then I started bringing other boards online till the boot process stopped. The switch matrix was clearly the cause of issues and I started going over all of them till I found the problem child.
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Waterbury, CT