I have a problem with my iPhone 6. Now it does it randomly when I lock it and then unlock it. The screen goes negative/almost black and I can hardly see anything. It wont turn off (just piles the screens on top of each other and touch screen doesn't work) and when I try to reset it just becomes negative again. So what could be the problem?
Sometimes an iPhone has a black screen after iOS 10.3/10.2/10/9/ update, sometimes it can get stuck at black screen suddenly. The reason causes your iPhone stuck on back screen or negative screen can either software issues or hardware issues:
Below we list possible solutions for you to repair iPhone 7/7 Plus/SE/6s/6s Plus/6/6Plus/5s stuck on black/negative screen.
A software crash or confliction can cause your iPhone display to freeze and turn black. In this case, a hard reset can easily solve your problem.
To do a hard reset, press and hold the power button (also known as the Sleep / Wake button) and the Home button (the circular button below the display) together for at least 10 seconds to force the iPhone to restart.
After hard setting, your iPhone still suck on negative screen. Try to restore your iPhone to factory setting with iTunes.
If factory restore still can't save your black screen iPhone, you may have to repair the operating system of your iPhone. iCareFone is a professional system care tool for iOS, that can easily repair corrupted or missing operating system for iPhone 7/7 Plus/SE/6s/6s Plus/6/6Plus/5s. This method is especially useful for repairing iPhone stuck on back screen with Apple logo/white logo/spinning wheel.
With the 3 methods above you are to fix your iPhone stuck on black/negative screen caused by software issues. If your iPhone black screen is caused by a hardware problem, make an Apple Store appointment to have a fix.