What are the reasons for the Audi A4 screen not lighting up?

[StMalachi]

Audi A4 screen not lighting up may be caused by the following reasons: Low voltage: If it happens occasionally, it's normal because during engine start, most power is used for ignition. If the voltage is too low, it may cause the screen not to light up. Abnormal power supply: If the screen frequently fails to light up, you should check whether the display's power supply is normal. If the power supply is abnormal, the power module needs to be replaced. Faulty cable connection: You can check whether the cable connection is good. If there's a problem with the cable, it needs to be replaced. If the cable connection is normal, then the display screen may be damaged.