Connect the laptop with an uninterrupted power supply. Switch on the laptop and charge until the battery is charged completely. Check the battery status by clicking the battery icon on the screen. Disconnect the power supply and restart the laptop. Connect it to another laptop or computer using an HDMI cable. Open the HP PC Hardware Diagnostics UEFI by pressing the F2 key repeatedly. Click the Component Tests option under the Home menu. Select the Hard drive from the list and click the Extensive Test option, and then click Run to begin the test. Wait until the test completes and the battery drains once the test is terminated. Reestablish the power supply. Recharge the battery and run a battery test. The black screen occurs due to some other reasons. They are problems with graphics driver and issue in the LCD backlight. Connect an external monitor or display with the laptop. Refer to the user manual for steps involved in connecting the laptop with an external monitor. Restart the laptop. If the screen does not display on the external monitor, then the graphics driver is having some conflicts with the LCD display. Download and update the graphics card to the latest version. If the screen does not display on both devices, then the problem is with the start-up process. Remove the power cable from the power supply. The laptop displays a black screen. Switch off the laptop using the power button and leave the lid open. Press and hold the Power button at a stretch for 30 seconds. During this time, the laptop turns On and turns Off repeatedly. Release the power button. Now, plug in the AC power and turn on the laptop. Click Start Windows normally on the Start page and press Enter. Check if the issue is resolved. If the issue is not resolved, go with the forthcoming steps. Remove the rear panel of the laptop. The RAM chip is inserted between two pull-out chords. Take the chip out by pulling the chords out. The battery is located at the top with a Lock switch. Unlock the battery, push, and remove it. Connect the laptop to s power supply. Press the power button until the fan stops. Reinsert the RAM chip and the battery. Switch on the laptop and the issue will be resolved this time.