I retrofitted the nav to my car a couple of months ago and it was all working perfectly, I just wanted a pristine screen as mine had some surface scratches. All of the components of my system were either new or refurb/remanufactured and so I'm skeptical that it's something besides the monitor itself. All Jimmy said he did was replace the screen and he said he tested it and it was working perfectly. I had asked him who made the LCD screens he had, which he said were oem, and he said, "some Japanese company," so I didn't get positive verification about the origin of the screen, but it could still be Sharp. I'm having a BMW technician remove and replace the monitor into the dash in a few weeks from now to see if it just a matter of how I placed it in - maybe it's pushing up against some cable that's causing it. Again, there are faint white lines going in a downward direction very fast, which move with the engine signal (they disappear if when I shut off the engine) - they're not even real easy to see, it's just that it wasn't an issue before I had the work done, and I've sunk so much money into this system, I want it to work perfectly..