Hardware GBA games get corrupt and glitchy at some point during gameplay and menus.

[SamsaSams]

Hi there! So I have this problem where my GBA plays GB/GBC games perfectly but GBA games get corrupted and glitchy in different ways during gameplay and in menus. GBA splash screen always looks good and most games load correctly, but once inside gameplay and menus the games get corrupted. Each game breaks in the same exact way and in the same exact point in time every time I try to play it.

Here is an example of what is happening to me, testing with the Pokémon Pinball GBA game.:


As you can see in the video, Pokémon Pinball Ruby and Sapphire breaks upon entering a board, and it always breaks in the same exact point. You can also see I'm using a flash cart, but I get the same problem in both ROMs and original cartridges so it's not a problem with the flash cart. I've also tested the flash cart in my GBA SP and it works correctly there, so the flash cart being a problem is completely out of the question. I've also tested with the original screen and I get the same results so it is not a modding issue because of the IPS display either.

Something particualr to GBA games is broken on my GBA. Any idea what could it be or how to fix it? I have a couple of GBA SP for spare parts, if those are compatible.

 

[Andrezin0692]

Weird, maybe one of the pins on the connector has a bad connection or is shorting out.... maybe there is a method to cleaning it. Also the battery not sending enough voltage to the cartridge?

 

[FAST6191]

GB/GBC has a slightly different pinout to GBA.
Similarly same point would speak more to an issue with a handful of pins; if it can't load the data it needs then crashing is the most likely result, and would happen at the same point as presumably the same data gets read each time
It working on another GBA would also eliminate the cart itself as an issue.

Voltage concerns, especially with a modded screen and some flash carts, are also present. However if it does GBC it should hopefully do GBA, and most issues there present themselves way earlier than potentially several minutes into a game.

So yeah cleaning pins, or maybe putting a bit of paper behind the flash cart PCB to make better contact with some pins maybe not there.
I would hate to have to scavenge a GBA SP cart slot from an existing board (desoldering and soldering a replacement is not so bad, desoldering an existing one and having it available for reuse... doable but I don't relish the prospect where I would happily do a DS one) but it could be done and replacements seem fairly few and far between compared to what they were some years ago.

 

[SamsaSams]

Weird, maybe one of the pins on the connector has a bad connection or is shorting out.... maybe there is a method to cleaning it. Also the battery not sending enough voltage to the cartridge?

So I wouldn't think it would be the battery as I've tested using new 1.5v batteries and the stock screen and I got the same results (I didn't record that test though). The contacts on the other part... maybe? I can try and clean it, or I can try and buy a cheap replacement online and test.

GB/GBC has a slightly different pinout to GBA.
Similarly same point would speak more to an issue with a handful of pins; if it can't load the data it needs then crashing is the most likely result, and would happen at the same point as presumably the same data gets read each time
It working on another GBA would also eliminate the cart itself as an issue.

Voltage concerns, especially with a modded screen and some flash carts, are also present. However if it does GBC it should hopefully do GBA, and most issues there present themselves way earlier than potentially several minutes into a game.

So yeah cleaning pins, or maybe putting a bit of paper behind the flash cart PCB to make better contact with some pins maybe not there.
I would hate to have to scavenge a GBA SP cart slot from an existing board (desoldering and soldering a replacement is not so bad, desoldering an existing one and having it available for reuse... doable but I don't relish the prospect where I would happily do a DS one) but it could be done and replacements seem fairly few and far between compared to what they were some years ago.

I think there are cheap replacements for the cart slot online that I could buy and test, but I will clean it and try the paper thing first and let you know.

My main concern is if the problem ends up not being the cart slot and it being a problem with some chip on the GBA board that's more difficult to replace.

Edit: So I got it working! I tested cleaning the cartridge slot and that didn't improve things. I tested the paper thing but no dice. I was then out of ideas and watching this video and the person repairing their GBA SP apparently had the same glitchy games problem as I did.

He noted it was definitely a CPU issue and fixed it by repairing some contacts on his CPU chip. I didn't have the tools the person on the video has but I tried reheating the contacts with my solder one by one and that fixed the issue.

Thanks for the help!