Please try the below mentioned steps and see if the problem resolves:
1. Connect the AC adapter to a known good power outlet. Check Power LED indicator on AC Adapter with/without plugging into the Notebook.
2. If LED on the AC Adapter goes off only after connecting to notebook, the issue is with the motherboard.
3. If the AC Adapter LED is ON, then remove external peripherals, battery, AC Adapter and press and hold the power button for 10-15 seconds to drain Flea power.
4. Plug in the AC Adapter and battery and check if the computer powers on.
Do reply with results.
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