Were you doing anything to the pin? Pretty easy to bump something.
According to the switch matrix for demolition man that's your plumb bob tilt.
https://www.pinitech.com/switch_database.php?name=Williams_Demolition_Man
Unhooked all of the column and row pins from the CPU...still nothing. Nothing works. Machine fires and just pops balls out.
Quoted from joekiss:Unhooked all of the column and row pins from the CPU...still nothing. Nothing works. Machine fires and just pops balls out.
No playfield switches or optos work if you remove the column and row connectors from the CPU.
The question that LTG inquired about is one to answer. Did the error message disappear?
I unhooked 2 pins from the CPU and turned the machine on. I cant get to the test mode.Of course nothing worked. Everything else fired OK
Plug everything back. Then start the game and go to switch matrix. Then unplug the bottom 4 connectors from the CPU board (J206, J208, J205 and J212). Is all the matrix with dots? Or do you have some squares? From my knowledge if you have all dots you are good. Then take a wire and connect pin 1 from J206 to pin 1 from J208. You should get a dot (11 from the switch matrix). Check all possibilities. If you only get 1 dot and the right one each time, your CPU board is good.
I do not have so much experience so I could be wrong. If there are people with most experience following this please correct me if needed.
Quoted from joekiss:Unsure. When the connectors are unplugged I can't get into test mode.
We are aware you cant get in test mode having the connectors disconnected. What does show on the DMD when you turn on the game?
Quoted from PinballManiac40:We are aware you cant get in test mode having the connectors disconnected. What does show on the DMD when you turn on the game?
When pins are disconnected machine turns on and runs as normal. Cycles through high scores etc.
Just put the claw and motor back together. Pin 4 which is the column row was a little burnt on the board and wasnt making a good connection. Cleaned it up as much as i could. Again this is how the cryo-board looked before.
So now with the pins connected back into the CPU I cant get back into test mode.
IMG_20200723_103327 (resized).jpgIMG_20200723_103346 (resized).jpgIs this when F114 and F115 blew?
Also it would be nice to see a picture of the opto board that is under the playfield.
Yes. I turned the machine and both fuses blew. I replaced them and got the error messages. Which opto board are you referring to?
It looks like your U20 is burnt. With power off, can you measure the resistance from Pin 9 to 10? It should be well over 2 meg in resistance. If anything lower, replace U20.
Quoted from joekiss:Which opto board are you referring to?
Quoted from joekiss:What is pin 9 to pin 10? Nothing is labeled on my CPU. Thanks a bunch.
U20 pins 9 and 10. U20 is the ULN2803, 18 pin IC.
Pins 9 and 10 are on the bottom 2 pins opposite the notch in the top edge of the part.
20200727_000458 (resized).jpgYour 12V is shorted internally in U20.
Now what really caused all this and your F114 and F115 to blow? Likely something on the switch column 4 is shorted to a GI socket, flasher, coil, something metal, or working on the game with power on.
This is why I was asking whether you were working on the game with power on. It helps to eliminate any potential shorts to the column 4 switches.
Like t said before I hooked up the cryoclaw board then turned the game on. Maybe something was touching? Either way the board is removed. I will order a replacement board. Thanks. Gotta find that part now.
Quoted from joekiss:Like t said before I hooked up the cryoclaw board then turned the game on.
Just trying to get it clear in my head is all.
Quoted from joekiss:Maybe something was touching?
There is a good chance of that. I think you need to inspect all the switches in column 4 for anything that may be touching a coil wire, GI lamp socket, flasher socket, insert lamp socket, flipper power, or even pinched wire near the switch to something metal. Something of this nature would be a cause....a different voltage shorted to a switch.
Quoted from joekiss:I will order a replacement board.
I don't see enough current within this board that would cause the problem. Can you do a diode test on D1 and D2 to be sure they are measuring between .4volts and .6volts?
You can remove the U20 out of the IC socket and test the resistance on the IC socket with the part removed to be sure it is measuring over 2meg resistance on pins 9 and 10.
Then you can measure the resistance on U20 pins 9 and 10 off the board to see that is measures the 176 ohms you measured yesterday.
That will definitely prove the U20 has an issue and that the board is ok without U20 installed.
My communication is awful. If that first quote came across as snarkey that was def not intentional.
Didnt mean replacement board meant U20. On marco and on Pinball life both say u20 is common cause of Ground Row Short https://www.pinballlife.com/williamsbally-uln2803a-switch-matrix-driver-chip.html
I havent messed with anything else except the cryoclaw which has to be completely disassembled each time I mess with it. I assume something touched. Either u20 is a couple bucks. Shipping will cost more. Thanks for the help!
I think the concern here is that if something is shorted and you haven't fixed it you will blow U20 again as soon as you replace it. If that is still your plan maybe pick up a couple?
Quoted from bam10:I think the concern here is that if something is shorted and you haven't fixed it you will blow U20 again as soon as you replace it. If that is still your plan maybe pick up a couple?
Exactly. Definitely want to inspect all column 4 switches before turning on the game again once a new U20 is in there. I would buy 10, but that is me. haha
Don't forget to get more F114 and F115 fuses if you're running low.
Great point. I am the first to admit i dont know much about the boards. Hopefully thats the first and only thing to blow.
Quoted from joekiss:My communication is awful. If that first quote came across as snarkey that was def not intentional.
No biggie. I see you may have implied not working on it with power off between posts #19 and #20. I just wanted to be sure. I was hoping that is what really happened. But since the game is off, you have more digging into the game to do to be sure there is not a problem elsewhere.
On that opto board, can you measure resistance across C1 to be sure it is not shorted? I would not think it is since it has not leaked out any of its electrolyte. I would change it too.
Quoted from joekiss:There is no C1...
[quoted image]
The one under the playfield I mentioned earlier in the thread.
On that opto board test, D1 and D2.
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