Hi, I have and mac book air 820-3437 with blinking, flashing display I measure Q7707 where I found pin 5 voltage going in and out from 3.3 to.09 soi change the backlight driver and all its resistor around it am still getting flashing backlight I check R7789 and R7788 and the resistance is good I replace the LCD display with another good working one still the same problem even change the LCD cable still problem remains I measure led return for 0 ohms and there good please help thanks.