Hi Guys,
Another Fix if the above don’t work require you to go inside the iphone as this happen to me after replacing a battery, half the screen was dimmed and I fixed it by
# remove the screen
# Pop the battery (so it doesnt discharge)
# remove the connectors to the screen ( see this tutorial) - [guide|51380]
# Blow dry it with cool air not heater - just in case there is any liquid
# reseat the screen connectors being careful to ensure there it a firm click in place for each - one thing to note is to remove tension off the cables by not having the screen at 90 degrees when replacing the connector protector plate, instead around the 75-85 range. this is just incase the connector slightly unseats which is what expect the issue was with my first attempt and getting the display not showing right
# reconnect the battery and start up
Hope this helps if the more simple methods fail