The issue, which causes purple vertical lines to appear on screen when the MacBook lid is open at a certain angle, has been seen on several MacBook models, according to repair specialists. “It’s a common problem, we get several of them a week,” Stephan Steins from repair shop NotebookNerds told me.
The problem appears to arise from the screen flex cable, which connects the display to the main body of the laptop. At the hinge point between the screen and keyboard there’s a gap that can collect dust and dirt. Debris then gets onto the cable and, through opening and closing the lid, damages the cable over time.
This, repair specialists say, is what causes the purple lines fault that can be difficult and expensive to repair. Check out a demonstration of the fault in this iCorrect video and the image above.
Below are pictures from a repair. The left image shows the damaged flex cable, while the picture on the right shows where the dust collects that leads to the fault.