What's new
Pinball info

Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!

12v unregulated blowing during gameplay on AFM

David_Vi

Site Supporter
5Years
Joined
Sep 3, 2019
Messages
4,205
Location
Sudbury
Our AFM has been faultless for years...till the very final game at our league meet when everyone else was left. Someone was having an epic game, the flippers and dmd died (it's a pin2dmd).

12v unregulated fuse had blown on the power driver board. I've replaced it twice and it's blown during gameplay. A third time I reseated all the ribbon cables and a few connectors and used auto burn in to test it. About 3 mins in it blows again.
I have tried it without the pin2dmd plugged in and get the same result.

During the league a flipper died, the baseplate had cracked at the coil stop end, so I had the playfield up to replace the baseplate before our evening competition. Other than that it hasn't been touched.

I just tried a burn in test without the playfield coil drive connectors plugged in and the fuse has survived. So could it be a coil, a diode? Everything works, until it doesn't.

I don't think the unreg 12v has anything to do with coils so it might be a red herring. Any advice appreciated.

Cheers
 
Last edited:
In the games proceeding the fuse blowing today I did notice a lock being triggered and a ball being fed to the shooter lane in single ball play.

Those are options and 12v unreg is related to those. But I am not sure what to make of it
 
It's a strange one, it would blow during auto burn in within 5mins yesterday, I did some poking around and haven't been able to replicate it today. I disconnected the two slingshot coils as they had connectors and the fuse survived but it must be a red herring as coils don't have anything to do with 12v unreg? Unless I'm wrong. But I've reconnected the coils and giving it another burn in now with no fuses blown yet.

I suppose I need to play some epic games to give it a proper thrash, the burn in isn't as chaotic as on other games I've used it on. Definitely not a proper load like playing it.

It’s knackered completely. No way to fix. Just get rid and sell it to me cheap. 😜

You don't need any more pins😄

Unplug the mothership PCB does it still blow?

Haven't needed to yet, it seems ok at the mo🙄 if the fuse was reliably blowing every game or test it would help. It feels like I'd have to test it for hours to be sure and then try eliminating a different 12v unreg connector

Failing Rectifier diode on load possibly

The four fat diodes right? I've ordered some of those incase. Plus 10000uf for C8 as a backup.


These sort of intermittent electrical faults aren't my favourites.
 
@Arv wins.

I just had an epic game, then it died. I put a new fuse in and immediately it blew. So now the short is permanent.

Second time there was smoke from the saucer.
A screw that mounts the led board to the saucer was laying on the board and moving about.

The little cap shows signs of burn, but I wonder if anything else was damaged. It's a gozmod board, is Martin still around here? Maybe he could help me diagnose and replace what's needed?

PXL_20260114_143335120.webpIMG-20260114-WA0047.webp
 
Back
Top Bottom