There's a short circuit in the system somewhere.  Check the USB ports for bent pins -- failing that, it's time for either a new system or a replacement system board (the latter may argue for the former, given the cost and age of the system).  
The battery is dead. Charger light not on. Unplug charger cords then back in, charger light comes on, measures 12 volts. Plug back into computer charger light goes out when I open laptop lid. Bought new charger. Computer came on. Lasted 5 min. then died. Charger light out, unplug, put them back in,charger light goes on. Plug into computer, charger light on, open lid light goes out. No power. Any ideas?
Inspiron 14z 5423 battery and charger issue