Chosen Solution
Hello, I have a customer’s iMac in which he stated he heard a “pop”, and the screen went dark. I originally assumed this was the backlight fuse, which I was told is inside the display, and I have done the following and still no results. PRAM and SMC New Display (confirmed working on other unit) New LED DisplayPort Cable (tested on both displays) The Apple logo can be seen, but only under extreme light in a very very dark environment. External monitor is only functional when the LED is not connected to the unit. All 4 LED diagnostic lights are lit up when the unit boots. I’m leaning towards logic board or power supply, but I don’t know where to go from here. Any help or advice would be appreciated. Thank you!
There is a backlight fuse on the motherboard near the SATA connector. You should test it with a multimeter for continuity first.
I have a iMac with exactly the same issue. I heard a ‘pop’ and the backlight went off. External monitor works fine. Alle 4 diagnostic LED are on. Image can be seen on display with a torch. Did you have any luck reparing the iMac?
