Chosen Solution
I have this Mac that was given to me dead. I’m trying to fix and hopefully learn something in the process. I figured out it had a bad video card so I replaced that and now it works perfect on an external monitor and it even detects the built in monitor but it will not display anything on it. All 4 onboard diagnostic LED’s light up and the backlighting comes on but it is just a blank screen. The hard drive I put in it had Sierra on it which works great with external but maybe it doesn’t support the LCD? I replaced the LCD just in case it had a problem with the same results. I will attach a pic of the system log because it will endlessly repeat the same thing and I don’t know what it means exactly. I do have the Snow Leopard DVD but I can’t figure out how to get it installed. Any help will be greatly appreciated!!!!
Use a flashlight to shine into the display are you able to see the faint images of your desktop icons? If you are the LED driver board. If not the LVDS display cable needs to be looked at as well as the logic boards connection as you likely damaged it in the opening process.
