The reasons and solutions are as follows:
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1. Use a multimeter to check whether the socket is normal and whether the power supply voltage is 220V. If the mains voltage is abnormal, you are advised to perform an environment test.
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2, use a multimeter to check whether the output voltage and current of the power adapter are consistent with the label. If the gap is very large, and the mains voltage is normal, you can judge that the power adapter is faulty, need to replace the laptop power adapter.
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3, if the above check is normal, remove the laptop battery, do not connect the external adapter. Press and hold the laptop power on button for 5 seconds and repeat 3 times. After releasing the residual charge of the notebook, insert the power adapter separately and power up the test.
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4. If the fault persists, check whether the power interface of the notebook is abnormal. Such as loosening or appearance damage.
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5, the above checks are normal, basically can preliminary judgment is the laptop motherboard fault. Recommended to the repair service station