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I received 2 13” Macbook Airs in need of repair: a 2014 model with a cracked (but semi-working) screen, and a 2015 model with water damage, which caused its backlight to fail (but it did work using a flashlight). When I disconnected the LCD cable from the water damaged Macbook, a few pins on the right side looked slightly damaged, presumably corroded. Wanting to make sure that the backlight issue was caused by a logic board issue, I then swapped the logic boards and connected the water damaged logic board to the cracked LCD. Same thing: no backlight. Here’s where I made a mistake: to check if the screen on the water damaged Macbook Air was salvageable, I then connected its damaged connector to the good logic board from the other Macbook. I got no image when booting, and then noticed a faint burning smell. I disconnected the battery, and realising I might have made a very bad mistake, I swapped the boards again to see if there was any damage. Now, the “good” logic board connected to the “good” (but cracked) screen no longer shows a backlight. With a flashlight, I can see the cracked (semi-working) screen. So I basically broke something on the 2015 logic board by connecting a bad LCD connector, causing the backlight to break. Is there anything I can check / do?
iphone3ghulp yes, you did. It appears as if you managed to shorten out at least the backlight circuitry. To begin the troubleshooting, you will now have to check the board connector and see if it got damaged as well as check the backlight fuse to see if it has failed.
for further identification etc. it might be helpful if you post some good images of your board with your question. Adding images to an existing question
