Chosen Solution
The Mac starts up and runs probably on thunderbolt to vga adapter but the built in screen remains black. It has an AMD HD 6770m graphics card so not the one under the repair program. Any ideas what could be the problem?
See if you shine a flashlight into the display at a sharp angle if you can see the faint image of your desktop & an external display works, then you know the LCD’s backlight services needs repair. But, … Without knowing which model you have I can’t tell you more.
