If a Lenovo laptop will not turn on, start by checking the power source by ensuring the charger and cable are working and properly connected, and try a different outlet if needed. Perform a power reset by disconnecting the charger, removing the battery if possible, and holding the power button for about 15-20 seconds before reconnecting power. Check for signs of life such as LED indicators or fan noise, and try booting without external devices attached. If the screen remains black, test with an external monitor to rule out display issues. If none of these steps work, the problem may involve internal components such as the battery, motherboard, or BIOS, and professional repair or service may be required.

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