Hardware GBA SP Boot issue

[LanHikariDS]

So, just had a weird issue come up with my GBA a few minutes ago. I got Metroid: Zero Mission today, so of course, I wanted to play it. I went and got my GBA from my dad, who was using it for some of his classic Game Boy games, and when I got it back and popped in Zero Mission, instead of booting up like it normally does, it showed the GBC Boot screen, with a black square over the Nintendo logo, like it does when a game doesn't read right, but is still recognized as a classic Game Boy game. I pulled out the game, lightly blew it, and the GBA, and tried again: Broken GBC Boot screen. I then tried turning it on without any game it, to see if it was an issue with the game: Broken GBC Boot screen. I then decided to see how it would react to a Game Boy game, went back, and grabbed a random Game Boy game from him: Tetris. It showed the GBC Boot screen, and the Nintendo text showed up properly, and it went into the game. I turned it off, took out Tetris, and turned it back on: GBA Boot screen, no Nintendo logo, as no game was present. It still worked after I put Zero Mission in, so I'd say it still works.

Just figured I'd document my experience and solution in case anyone else experiences this, as I couldn't find anything about it online right away (Though, I didn't look very hard...)

 

[FAST6191]

Look inside the GBA slot. Hold it so the label of the game would be pointing downwards in normal play (should work for the GBA or SP). On the left there will be a small slide switch. This occasionally gets gummed up with dust and stuck a bit. Said switch is also what tells the GBA to boot in GB/GBC mode.

If you want put a GBA cart next to a GB/GBC one, labels down in both cases. See the lack of a notch on the left hand side at the pins end of the cart? Best if you do not force it though as GB/GBC mode uses a higher voltage than GBA mode (one of the main reasons you can not use a GBA flash cart as a GB/GBC cart) and that is not great to do for long periods of time.

 

[Deleted-236924]

You sure your Zero Mission cartridge isnt a bootleg?
I ask, because maybe a bad bootleg could be shaped a bit differently from legit cartridges, and the notches on the cartridges might not be big enough and the cartridge would end up pushing said pin down anyway even though it's a GBA game.

Got other games you know are legit that work on it? Or do they all behave the same?

 

[LanHikariDS]

You sure your Zero Mission cartridge isnt a bootleg?
I ask, because maybe a bad bootleg could be shaped a bit differently from legit cartridges, and the notches on the cartridges might not be big enough and the cartridge would end up pushing said pin down anyway even though it's a GBA game.

Got other games you know are legit that work on it? Or do they all behave the same?

I tried my Chain of Memories cart before Tetris, and it brought up the GBC boot. And again, it couldn't be Zero Mission, because it happened without a cartridge in it at all.

Look inside the GBA slot. Hold it so the label of the game would be pointing downwards in normal play (should work for the GBA or SP). On the left there will be a small slide switch. This occasionally gets gummed up with dust and stuck a bit. Said switch is also what tells the GBA to boot in GB/GBC mode.

If you want put a GBA cart next to a GB/GBC one, labels down in both cases. See the lack of a notch on the left hand side at the pins end of the cart? Best if you do not force it though as GB/GBC mode uses a higher voltage than GBA mode (one of the main reasons you can not use a GBA flash cart as a GB/GBC cart) and that is not great to do for long periods of time.

I don't need help. As I said in the first post, the problem was fixed before I wrote, but I still felt I should document it here.

 

[FAST6191]

Sorry, I meant to preface that by saying we have seen this sort of thing before and this was what it usually turned out to be.

 

[RetroBro2317]

Sorry, I meant to preface that by saying we have seen this sort of thing before and this was what it usually turned out to be.

I am having this issue right now… I located the switch in the SP and was like wtf is this!? Anyway, I got it to work and start up sapphire after letting it sit for a few hours.. could a wet or moist CPU cause this?? I only ask this because I did wipe around the board with some 90% isopropyl and was thinking of what else did I do different?? I did do a charging port mod to type-C but everything was checking out normally. Fuses are good and I don’t see anywhere in the motherboard where a stray solder is or a broken one at that. I need some pointers please, thanks in advance.

 

[FAST6191]

I am having this issue right now… I located the switch in the SP and was like wtf is this!? Anyway, I got it to work and start up sapphire after letting it sit for a few hours.. could a wet or moist CPU cause this?? I only ask this because I did wipe around the board with some 90% isopropyl and was thinking of what else did I do different?? I did do a charging port mod to type-C but everything was checking out normally. Fuses are good and I don’t see anywhere in the motherboard where a stray solder is or a broken one at that. I need some pointers please, thanks in advance.

Sit powered or sit powered off? Equally does it charge?

If it is powered on then my thoughts would be towards dodgy capacitors. Powered off then more likely a bad joint somewhere that just so happened to line up after a period off, might also work if you turned it on upside down if gravity helps make a tighter connection.
No idea which connection or capacitor it might be that causes this one, and frankly with the age of these devices it could be almost anything in there. Dry joints do not always appear obvious either.

Trapped moisture might but IPA is fairly quick to evaporate and does not conduct electricity so well in the first place. Should not get trapped under the CPU either like some