Unfortunately, this is a hardware failure. No software diagnostic tool can erase a physical line. The screen assembly must be replaced. Screen Flickering and Strobe Effects
If the dialer code is disabled, the official Samsung Members app provides the exact same diagnostic capabilities through a modern user interface. samsung galaxy diagnostics screen tool fixer
: Independent tests for the receiver (top speaker) and media speaker help isolate sound quality issues. Unfortunately, this is a hardware failure
Turn off your phone. Connect it to a computer via USB cable. Hold Power + Volume Up until the recovery logo appears. Use volume keys to select Wipe Cache Partition and confirm with the power button. This deletes corrupted temporary system files causing UI stutters. Screen Flickering and Strobe Effects If the dialer
Similar to the secret menu, this prompts you to draw on the screen to map out touch sensitivity and detect dead zones.
The diagnostic menu is a powerful tool, but it cannot fix physical damage. If your screen fails the grid test entirely, or if solid color screens show deep black bleeding spots, the internal OLED panel is broken. In these cases, the phone requires a physical screen replacement at an authorized service centre. To help find the right troubleshooting path, tell me:
You can open the menu using your phone app.Follow these simple steps: Open the app. Tap the Keypad tab. Type *#0*# into the pad. The menu opens instantly. Note: This code may not work on some carrier phones. How to Open Diagnostics via Settings