Alexandre Fernandes Nicoli, there are a few things that could be causing this. The very first thing I would try is a new battery. Then check the connector, look at it closely and see if there is any definite damage, broken pins etc. If it looks ok and you have a new battery, see if it charges. If not then you have to take the GBA apart. check for lose connections on the charger. Use a multimeter to see if it gets power when you plug it in. The GBA has two fuses, marked F1 and F2 ion the logic board. Check those with a multimeter and see if you have continuity. Replace those as needed. Hope this helps, good luck
Image shows F2. F1 is on the opposite side of the board.
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What charger did you use before? Did it fit the connector properly?
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