Psp 15 seconds then off

[soccerjer64]

My friend has a psp that turns on only with a green light and with no sound or display. I tried to fix it for him with pandora's battery, but when the pandora battery boots up and I try to downgrade/upgrade it, the files start to write for 15 seconds then the psp shuts off.

What could be the cause of this?
How can I fix this?
Any ideas would be greatly appreciated.

[mike_jmg]

did you plug in the AC adapter?
are you sure your pandora works, tried another psps?
How did it brick?

[soccerjer64]

The psp orange light blinks then freezes/stops when the psp say loading psar to ram using pandora.