I hadn't used the PSP-2001 for about 6 months. When I tried to charge it the orange light stayed on overnight. I removed the charger, and the unit wouldn't power on. I ordered a replacement battery. Now the unit will ONLY power on when the charger is attached. On the PSP home screen there is no Battery charge symbol; and also no Battery Information in System INFO. As far as it is concerned there is no battery present.