1. Faulty display: The LED display itself may be faulty and need to be replaced.
2. Loose connection: The connection between the stereo and the display may be loose or damaged. Check the wiring and make sure it is properly connected.
3. Software issue: There may be a software issue with the stereo that is causing the display problem. Try resetting the stereo by disconnecting the power source for a few minutes and then reconnecting it.
4. Damaged circuit board: The circuit board inside the stereo may be damaged, which can cause display issues. This will require professional repair or replacement.
If none of these solutions work, you may need to take your car to a qualified mechanic or car audio specialist to have the issue diagnosed and repaired.