Hi beswik07,
Please turn off the system and disconnect any attached peripherals (printer, Ethernet cable, USB flash drives, SD card, AC adapter and the battery). Press and hold the power button for 15-20 seconds.
Disconnect the AC adapter & try to power on the laptop on battery only. If it does not power on, disconnect the battery & connect the AC adapter; now check if the laptop powers on.
Please check if the Num Lock key, Caps Lock key & Scroll Lock key flash in a specific pattern as shown in the image.
Please try these steps and share the status.
Thanks and Regards,
Manpreet C
Hi i have a dell latitude 420 and have had it for nearly a year and half . my charger broke ( lead split) when i was in indonesia . i did not use the laptop obviously after the lead broke because i could not charge it. so after traveling with it and now being in Australia i brought a charger for the laptop. i plugged it in. the charging light came on ! but when i tryed to turn it on , even after fully charging the battery , i press the ON button and it flashes the bluetooth light and few more like it always use to do and then switches off ? can anybody help me with this ?
thanks joe

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic