I still today continue using my Mac display, but I have to occasionally unplug replug the power cable, so the problem still remains. I have ordered two LED strips to replace them when I get time to do it. I realised that adjusting the screen brightness to full before connecting the display to macbook helps for the issue often, but not always.

Update (2018/09) My display is still up and running after changing the Capacitors, but I reckon this is only coinsidense. I would advice you to have a look at James Stuart comment/explanation below. I think it makes the most sense and explains the cause of the problem well! James Stuart at: https://de.ifixit.com/Antworten/Ansehen/... “ I don't mean to offend anyone but you all seem to have missed the blatantly obvious and that is the LED backlight array. LEDs age, and as such the amount of light that is emitted reduces. The LEDS in the LM240WU6 panel are made by Lumileds which is a subsidiary of Philips who in turn produced the panel under license from LG. The LEDs used are LXML-PWN1-0120 which should be operated at a forward voltage of between 3.0V & 3.6V @ 350mA and have a stated 39000 hours of life. LEDs operate in constant current mode that is the current through the device is adjusted by altering the voltage across it. In low current LED applications this done with a simple resister. In high powered...

If the display is not even recognized by the system, I would try listening if even the fan starts to roll. Otherwise I would go further checking the power voltages first. But yeah as @SW said You might as well quick try and see the Panel with a flashlight if you have a weak image without background lighting.

Sounds like the same problem I had. See: What components need replacing on the Logic board?

I would guess that if the display is not connected to the laptop video output the display shutsdown/ power save mode => switch off the LCD voltages => I havent checked the TP11 but I guess it goes to the LCD or LEDs. if you read the issue: What components need replacing on the Logic board? You will find an an extensive description on the LED background not lighting. If you have any questions just ask and I ll see what I can find out but please read the thread carefully, I think you ll find your answer there.

Ich habe das gleiche problem gemerkt und dann habe ich in service manual gesehen das der verursache war falsch versteckte sensoren im Logic board. Der display temp sensor und der andere blower sensor sind vermutlich verkehrt.