No display on macbook Air 2017 and Macbook Pro 2015 | Macbook Black screen repair Backlight IC

[@angelmoreno6649]

brother, I need your help, I have an imac a1419 (2014) that drives me crazy, it does not provide audio, the strange thing is that it does provide audio when the machine starts, once the system starts, it does not do so, it does not detect any device, except one that says digital output, I have already ruled out the system, I already changed the headphone jack, I measured if voltage was reaching the codec, and if it did, (just in case I replaced it) and the problem continues, I no longer know what to do, thanks in advance .