Outdoor LED advertising screens can experience various malfunctions. Here are some common issues:

1. Dead Pixels: Dead pixels are individual pixels on the screen that fail to light up. This can result in small black or colored spots on the display, affecting the overall image quality.
2. Uneven Brightness: Sometimes, certain parts of the LED screen may have uneven brightness or color consistency. This can be caused by faulty LEDs or improper calibration.
3. Flickering: Flickering can occur due to issues with the power supply, or it could be a sign of aging or defective LEDs. Flickering can be distracting and negatively impact the viewing experience.
4. Image Retention or Burn-in: If static images or logos are displayed for extended periods, image retention or burn-in can occur. This leads to a ghosting effect where the residual image remains visible even when the content changes.
5. Temperature and Weather Effects: Outdoor LED screens are exposed to harsh weather conditions. Extreme temperatures, moisture, and direct sunlight can damage the screen, causing discoloration, decreased brightness, or complete failure.
6. Connectivity Problems: Issues with signal and data connectivity can prevent the proper functioning of an outdoor LED screen. This can include problems with cables, controllers, or network connections.
7. Power Failures: Power surges, fluctuations, or total power failures can occur, leading to the screen not turning on or displaying any content.

Remember, regular maintenance and professional servicing can help prevent and address these malfunctions, ensuring optimal performance and longevity of outdoor LED advertising screens.