um ok, lets see if i can help
firstly what happened? what caused the psp to start acting up? (did you buy it like that?)
and secondly are you the person who created the Pandora battery and mem? If memory serves me right (its been a good couple of years) the battery needs to be a psp1000 one and once you put it in it's normal that screen doesn't show. I mean it works and all, but you need to remember which button to hold and how to navigate the menu without looking... i think. After that recover the psp though the menu, instal CFW and pop the normal battery in.