These things aren't designed to be repairable. Electronics repair these days amounts to basically removing whichever circuit board is bad, and replacing the entire thing.
And given that places like GameStop are practically giving away any GBCs they may still have in stock, heck, they're practically giving away any GameBoy Advances they have, it just doesn't seem worth the bother. Even if you managed to find someone selling theirs for parts, there's likely really only one circuit board in the GBC, so if theirs is broken, it won't do you any good.
I'd say go to a local GameStop or online, just get a GBA. They play all GB/GBC games, and you can expand into GBA games.
Well a few years ago, if my memory is correct, I accidentally submerged my game boy color in water. I think I just left it to dry after that. Anyway, after that it didn't work 100% properly and I'm pretty sure what is happening now is caused by the water damage.
What it actually does is, when I turn it on with a game in it it gets to the loading screen (the word "Nintendo" at the bottom of the screen sometimes glitches here and shows as glitched text or just a black bar) and then it rarely passes this screen. The only time it does pass this screen is if I have Tetris in, and then it's a 50-50 chance as to whether it plays the game or it just fades out from the loading screen and stays black. For all my other Game Boy original games (e.g. double dragon, pokemon red) it doesn't pass the loading screen, and with my gameboy color games (i only have 2) it doesn't even get to the loading screen and just turns on to a blank screen and stays there.
Does anybody have any idea how I can fix this? I've tried a bit of googling and Nintendos website but I couldn't find anything.
Thanks.
P.S. Also the sound doesn't come out from the speakers but it comes out from the headphones too, I would also like to be able to fix this.

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