gbasp ags001 does on for a second then off

i bought this gameboy as defective and the only issue that the screen has burnt, it turns on without any problem and can read games

i clean the motherboard cause it so dirty. after cleaning, now its not turning on completely, it turn off after a second.

i tried cleaning the power switch with 99% isop alcohol, nothing happens. i checked fuses and F1 has continuity and F2 has no continuity. i tried replacing fuse but it doesnt fix the problem. i also do trial and error in installing that, tried in reverse and vise versa but it seems it is not the problem

now i think it might grounded, but i dont have another sp for reference, i tried again cleaning but it doesnt help

when i connect it to the charger, charging indicator lights on, but the power still turn on then off after a second

the battery is still goods, it reads on my multimeter around 4v, im not sure if its normal cause i dont have much knowledge at electronics

EDIT: i tried again checking some connection using multimeter and after that, gameboy is not booting up, white screen only no gameboy logo and no boot sound, so its not the lcd problem.

all the things i do is just clean it and check with a multimeter and now its broken

EDIT 2: ITS NOW BOOTING UP! WITH A LOGO, but still turn off for a second and when its charging, just in a minute, it so hot the gameboy. and there is no voltage coming on battery port using my multimeter