Popeye - Random "Coin Door Open" DMD MSG During Game

[CUJO]

Popeye was giving me a credit dot two months ago.
The error was Ball Trough #2..
Bought a new ball trough transmitter/receiver board from Great Plains.
Still had the error. Then in switch mode, I was noticing that none of the ball optos switches were registering.

Long story short..fast forward two months to today.

I pulled CPU board and neutralized some very mild acid damage. Also replace all the lower CPU board connectors with new, all of them.
Some had some corrosion. Cleaned all the pins on the CPU board but they appeared very clean and new like.

Ok, so game plays 99% now. All switches work, ball trough happy BUT on occasion during the game, the DMD will STROBE OUT "COIN DOOR
OPEN"" with the dong dong dong sound you would hear if you were actually opening the door. Game will recover and play on most of the time.

Last night, it reset both players to start over in middle of game and didn't even notice it had happened till I looked up at DMD.
So I guess there's an IC up there related to the coin door circuit I need to cut out, install socket and replace IC.
None of them are socketed currently.

Any other suggestions on how to approach this issue would be appreciated.

[FUNWIZ]

Start with the lower left chip and work to the right, and keep replacing each one until you find the problem.  One leg on a chip has been eaten away probably internally, and will take time to find it.  GL

[CUJO]

They all don't look like they have had a bad battery acid scare..
Do you know if one IC is responsible for the COIN DOOR issue, possibly U20?
I might start there then...

[FUNWIZ]

You can start there, no guarantees, that won't cause a reset.

[CUJO]

Popeye played stable for a week, then my  better half tonight got the "COIN DOOR OPEN " during a multiball. DMD Message popped up 2-3 times but game kept playing and kept score without a reset.

I did notice that the bottom flippers were flipping weakly on their own during this 5-10 second travesty.

I know I have work to do on the CPU board IC's but was wondering if the flipper actuating during the COIN DOOR OPEN message
means anything as exactly what is failing intermittently?

[FUNWIZ]

Have you pulled U9, cleaned and reseated it?

[CUJO]

No, but I did press on it to reseat it. I don't have a chip puller for that monster.
If I pull the board out, I'll press down on a flat surface.
I played a long game yesterday with no incidents after pressing on it.
As I mentioned, it's very uncommon now for it to do what it did before.

[k7]

asic chips can cause some goofy 1-off errors. you probably/hopefully found your issue.

i purchased 5 asic chip pullers off eBay out of china and passed them off to friends. they are cheap enough, handy to have 1 on hand.



 

[CUJO]

asic chips can cause some goofy 1-off errors. you probably/hopefully found your issue.

i purchased 5 asic chip pullers off eBay out of china and passed them off to friends. they are cheap enough, handy to have 1 on hand.



 

Would you be so kind to send me the link to the ones you bought?
I love having extra stuff!

[CUJO]

This one?
http://www.ebay.com/itm/1PCS-PLCC-IC-Chip-Extractor-Motherboard-Circuit-Board-Component-Puller-Tool/221944834880?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26meid%3D094fc84a77b746148f9e2965045d78ed%26pid%3D100005%26rk%3D6%26rkt%3D6%26mehot%3Dpp%26sd%3D222189078280

[k7]

ya, that's basically it. you'll find a 5 pack for under 10 bucks on eBay.

[CUJO]

Found some time yesterday and had (2) 14 Pin DIP IC Sockets and (2) LM339's so took  U17 & U16 off the CPU board.
De-soldered the old pins and reflowed the holes. Seated/soldered in new sockets and inserted LM339's.
CPU board back in and played 5-6 games without an issue so did as FunWiz suggested. He suggested  replacing from left to right and two
was all it needed. (they looked the worse too)...I'm hoping anyway.

[FUNWIZ]

Hurray!  Sometimes boards get what I call cancer, and it can start anywhere, and creep around, depending on how tolerant the chips are and resistant to the acid from the batteries.  For now, probably fixed for awhile, but it's still hiding, and could be back in a year or two on remaining original chips.  Hoping that don't happen, but keep it in mind in the future.  You did the right thing, adding sockets, so repairs can be made quickly.  I like to get replacement boards that have that feature, as I hate changing soldered in chips.   

[CUJO]

Well although it's 99% better, I did get the COIN DOOR OPEN again last night during a MBall.
Ordered more 14Pin DIP sockets and LM339's. Going to start from the right side of the CPU board now.'
I hate Acid Damage!! Someone should make a T-Shirt!

[FUNWIZ]

Heck, maybe you also have a bad door switch, bypass it for awhile and see if it still pops up, or could be a poor connection to the switch.  Also put a meter on the +5v on the board, start a game and multiball, see if it drops, you might have a 5v dropout for a second or two causing problems.