Instructions
Plug in your PSP's power adapter to ensure that your PSP's battery is fully charged. During normal use a flashing green light indicates that the battery level is low. The power indicator light will turn orange while the battery is charging and will turn off when the charging is complete.
Press the "Display" button at the top of the unit to ensure that the screen's brightness setting is not the cause of the darkened screen.
Slide the "Power/Hold" switch up to make sure the PSP is not in "hold" mode.
Reset your PSP. To do this, remove the battery and wait 10 seconds before replacing it. Press and hold the two clear "L" and "R" buttons on the top corners of the unit while the system reboots into "Recovery" mode. Locate and highlight the "recovery" folder, then press "X" to reinstall the files.