Apologies ahead of time if this is the wrong place to be asking about this stuff- the problems I'm having aren't related to hacking really, but they are troubles I'm hoping I might be able to solve with more opening up of the game boys and what-not, and this is the best source I've found so far of anyone who might know about that.

I have a Game Boy Advance SP that went through water damage a few weeks ago. This has caused a litany of problems with the device that I'm still having trouble quantifying, but I'm hoping someone might be able to tell me why it does these things.

First, and most obnoxiously, the battery keeps acting wonky. At first I thought this was because of the water damage, but I played the SP with no frills over the last several days. It started acting wonky again after I opened it earlier this evening to try and figure out why it was acting so squirrely with the second problem. After apparently a little bit too much of that, it's gone back to acting strange. To be more specific about what it does- even if the battery and the recharge cord are plugged in, the power light and the recharge light will either not come on, or will come on very briefly and then disappear a few seconds later. Does anyone have any idea what technical problem could cause this to happen? How does the recharge wiring work in the SP? Is there anything that can be easily screwed up just by observing the system with the back taken off?

The second problem, and the one I believe led to the resurgence of the first, is that the L and R buttons seem to have lost functionality. Oddly, we were able to make the R button work after some trying- but doing so required pressing the button ridiculously hard. This might have been a cause of the water damage but it's really hard to tell- I can't seem to figure out what pressing those buttons is supposed to activate in the system. The springs in particular have a real muddled purpose. All I really know right now is that, for very limited R button capabilities, I have gotten a handheld that will not consistently turn on. I'd like to have one that can do all these things, but I'd settle for at least knowing what it is that's causing these problems.

Lastly, and this isn't a recent issue but more of an ongoing one, I have an old Game Boy Advance regular that suffered physical damage some time ago. Some games it can play in a very glitchy, largely unplayable manner and others it won't. A Gamecube can recognize it, but only with a blurred logo that continually tries and fails to reconnect. The controls still work, so my best guess is that something happened to it that screwed up its ability to read external data. But honestly, I have no idea- it would help a great deal if I knew which parts did what.

So, that's pretty much what I'm looking for. An explanation as to how these machines mechanically work so I can identify what's causing problems in them. Things like diagrams of normal working GBAs would be extremely helpful, as well as any sort of technical explanation for what, hardware wise, could be causing them to act up in such a manner. Any help along these lines would be greatly appreciated.

99.9% chance it is not mechanical but electrical and beyond repair.

Which problem? All of them?

I can understand that for the older model, but it doesn't make any sense as regards the newer one. Why did it work with no errors for the past several days only to abruptly decide to stop working after opening it for a spell to take a looky-loo?

Here are some suggestions that I would consider if I was in your place.

GBA SP
Shoulder buttons:
If you are having to press hard to get these shoulder buttons to work, that sounds like it could be a mechanical problem. The moving buttons that you press on may be too tight against the rest of the casing so that they are not free to move. I had a similar problem when I took apart my DS. You should make sure that the SP's case is closed up properly, so that both halves line up correctly and do not pinch the shoulder buttons differently than originally intended. Make sure that the shoulder button springs (if the SP version has any) are in the right position so that they do their job of making the button covers spring back out when not being pressed.

You could open up the case again and make sure that the insides of the plastic shoulder buttons are not dirty. They should be able to move freely and spring back automatically. If they are sticking, you could try running a knife blade through the cracks around the button (when the case is closed) to make sure there isn't any dirt or lint in there, and this also might help loosen up the buttons.

If that doesn't help the shoulder buttons work better, then you may want to open it up and look at the actual tac switches, the buttons attached to the PCB. Press them and make sure that you can feel them click. Check to make sure that they are connected to the board well and are not at odd angles.


Water damage:
Open up your case and let it sit open for a few days (in a non-humid location) to make sure all the water has evaporated.

SP Battery problem:
_Make sure that after opening up your SP case, you are aware of all the locations where an electrical connection occurs with the battery. Make sure that the contacts on the battery and the ones on the SP PCB are clean. most likely, the contacts on the SP PCB should have some kind of springiness or flexibility so that they make good contact with the battery when it is inserted.

_ Look over the circuit board, especially around the battery, charge port and power light areas to make sure that there are not any loose or damaged components, and check that the solder connections look good. Try wiggling the part holding the battery contacts and the charger port to make sure that they are connected firmly. If they are loose, that could cause intermittent problems as they move around.

Original GBA
These sound like electrical problems.
_Make sure that the cartridge contacts are all clean and undamaged.
_Make sure the screen cable is connected all the way
_Check for damaged or loose components, bad solder connections, or broken board traces.

So, minor update- we've been able to determine that the shoulder buttons were somehow damaged by the water beyond repair and will likely need parts replacements. I don't suppose anyone has any idea where such parts could be acquired? You all seem to be in the business of taking apart and reorganizing machines.

I know it would probably be easier to just buy a new SP but there's something charming and romantic about fixing the old one instead.

Forgot SMEXY :3
Lol

Try turning on the SP when the case is open (you might need to run it off the power cable), or remove the external shoulder button cover so you can directly press the switch on the circuit board. This should show you clearly if the button works, with no chance of interference from the plastic button cover.

If the button was damaged by water, as you said, and does not work, you may be able to replace it with a new tact switch. If you rip open a VCR that doesn't work anymore you can usually find lots of those switches behind the front panel.

I would guess that if you are real careful you should be able to unsolder the broken original button, and solder a new one on to the same contacts. You could glue/epoxy it in place after it is soldered down to make sure it stays there when you press it.

...or you could search online to find a replacement button to buy.