What does a DU blank screen indicate?

A blank display unit (DU) screen typically signifies a display unit failure. This issue arises when there is a malfunction in the DU itself, resulting in an inability to process or show the necessary data and information. In the context of avionics, a blank screen indicates that the display is not receiving adequate power, signals, or data, which is essential for its operation.

In contrast, a blank screen does not indicate normal operation, as the screen should be displaying various flight information and data. An electrical overload might cause different symptoms rather than a complete blackout of the screen, such as flickering or erratic behavior. Similarly, while a generator malfunction could affect the overall electrical system, it is more likely to cause a broader impact across multiple systems instead of isolating the problem to just one display unit. Thus, determining that the blank screen points to a failure specific to the display unit itself aligns with standard diagnostics procedures in aviation maintenance and operations.