Hi @tinasweetie
Does the laptop indicate that the laptop's battery is being charged when the charger is connected to the laptop?
''If not'' it may be a faulty charger or perhaps a faulty DC-In jack. If the charger is faulty it can't charge the battery to operate the laptop and also it can't run the laptop either. If the DC-In jack is faulty it is the same thing, the battery can't be charged and the laptop can't get any power from the charger so that it can operate.
First use a voltmeter and check if there's 20V DC at the output cable plug of the charger.
''If the charger tests OK'' then open the laptop and check if the DC-In jack has continuity from the input side of the jack to the red and black wires connected to a cable plug on the output side of the jack.
To do this you will need to open the laptop and remove the systemboard from the laptop as the DC-In jack cable is plugged in ''under'' the systemboard.
Here's the [https://download.lenovo.com/consumer/mobiles_pub/ideapad_p580_p585_n580_n581_n585_n586_hmm_1st_edition_apr_2012.pdf|hardware maintenance manual] for the laptop. Go to p.54 to view the procedure to remove the systemboard. On p.60 it shows how to remove the DC-In jack from the laptop so that you can test if it is OK or not.
If the DC-In jack is faulty then it cannot be repaired. It has to be replaced.
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