The screen changes colors to black, white, red, green, and blue.
Continue to hold the D key until you see the entire screen change colors. Press and hold the D key and turn on the computer to enter the LCD built-in self-test (BIST) mode.Ensure that the LCD screen is clean (no dust particles are on the surface of the screen).Disconnect any devices that are connected to the computer, and connect the AC Adapter (charger).When you notice screen abnormalities like flickering, distortion, clarity issues, fuzzy or blurry images, horizontal or vertical lines, color fade, running a diagnostic test on the LCD helps identify if the issue is with the LCD panel. Dell laptops have integrated diagnostic tools that can determine if the screen abnormality is an inherent problem with the LCD screen of the Dell laptop or with the video card (GPU) and computer settings.
