Gaming GBA SP Will not power on

[Rackover]

Hi
I'm trying to repair the GBA SP of a friend. It's a blueish-purple color. It has no visible damage anywhere. I cannot turn it on.
When plugged in, the orange light lights up and it charges forever. I assumed the battery was dead, so I bought a new one. The GBA sp then charged for like 3 hours, and then the led vanished.

When I try to power it on, nothing happens at all. I thought the issue would be with the power switch, even though it looks almost new, so I opened up the GBA and triggered the switch on the motherboard by myself. Nothing happens either.
What could the problem be, and is there another way to turn on this GBA SP ?

The motherboard looks clean and without damage, on both sides.

 

[Rackover]

 

[FAST6191]

Just as a quick check can you see what EM8 (probably underneath the ribbon) looks like
https://gbatemp.net/threads/gba-em8-component-missing-solution.540092/
https://gbatemp.net/threads/need-help-replacing-charging-port.502008/page-2

 

[Rackover]

It looks nice and clean. No visible damage.

 

[MichiS97]

Mostly, these kind of issues come from a dirty power switch. At least that's what I mostly experience (I buy broken Gameboys and repair them as a hobby).
If you've got a soldering iron, try and follow this tutorial:
The video shows a normal GBA but the SP uses the exact same power switch.

 

[Rackover]

I do not have a soldering iron. Is there any possibility for me to shortcut this system to simulate a power-on on the motherboard?

 

[MichiS97]

I do not have a soldering iron. Is there any possibility for me to shortcut this system to simulate a power-on on the motherboard?

No, not if the power switch isn't making contact, which is probably the case. You could try to get some 99% isopropyl alcohol, put it on a q-tip and just rub that q-tip into the switch. But that won't be anywhere near as effective. In my experience, if the switch is that corroded that the system isn't powering on at all, then only a full disassembly helps.

 

[Shadow-Zero]

Can you see any issues with the power switch from the outside? Or you really need to remove it?
I'm wondering if my SP AGS-101 has two issues. Currently:
- can't turn it on, nothing happens
- put the charger in, the orange light turns on for a split second, then dies off. Sometimes also the green light turns on for a split second together with the orange light


Checked F1, F2 and EM8 with a multimeter, that seems to be ok. Also tried a working battery from an other GBA-SP. Really puzzled currently! First owner, and the SP still looks pretty mint overall. Haven't turned it on for years, but same story for my AGS-001, which still works fine.

 

[FAST6191]

Some switches can be visibly observed as failing (I fixed a device the other day with such things actually) but this is one of the more modern enclosed type. You might be able to tell something with a multimeter but eh and results might vary more depending upon how good a contact you get between the pads you are measuring on. Some kind of high frequency source being sent through it and observed might tell you more but if you don't have a soldering iron you are not going to have such fun toys. You might also be able to bypass it by soldering something to the relevant pads but I am not sure what those might be or the pinout of the switch offhand.

That said unless the switch is forced closed (such that it is "powered on" at all times which would be rare) then that would not explain the behaviours of the lights.

 

[patters]

Check continuity across the fuse F1 I think it's labelled, near the power switch. I believe this often blows if the board gets wet.

 

[Shadow-Zero]

Like I said, checked F1, F2, and EM8, which all seem to be fine.

@FAST6191: I kinda assume a power switch issue would not relate to the GBA-SP not being able to charge. At least, various discussions I've read people say that it does charge, but they can't turn it on.