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So I was repairing a cracked screen on an iphone6s, but before beginning I forgot to shut off the phone, I did disconnect the battery however. Then once I finished the screen is black and won’t turn on with the power buttons. It occasionally flashes the screen for a second but then it goes black again. I am able to answer calls and charge it and it is definitely on but it doesn’t show dor nor than the rare second. PLEASE HELP ASAP I NEED TO RETURN THE PHONE BY TOMORROW!
The iPhone 6S is prone to backlight circuit issues when the screen is connected with the battery or power on the device. Have you tried re-installing your original, cracked screen? If that one works, then you have a bad replacement screen. If the original also has the same problem, then you probably blew the backlight circuit somehow.
