Answer to: Why says insert sim card?Possible broken tabs on sim card reader, shine a flashlight in the sim tray hole and see if any are broken or missing...
Answer to: black screen and green vertical lines after lcd replacementI have seen this a couple times in our shop. So far my co-worker and I have figured out that it is some kind of short on the board, After market screens will show the greenish weird vertical lines. Choice screens show nothing, however the backlight is lit up. The 2 phones we have encountered with this problem were iPhone 6. Both customers used car chargers religiously. The black out issue only became a problem when the battery was disconnected, and reconnected after a screen replacement. We have tested fuses and found none faulty. iTunes recognizes the phone, screen is still black. Besides the 2 we have in the shop, I have encounter at least 3 more with this issue. Those 3 were fixed using Rec Boot, a tool to place a phone in and out of recovery mode. I put those phones into recovery mode, and when I kicked them out of recovery that fixed them and the screen came back to life. The other 2 we are still working on to find out answers. Have not replaced the backlight filter fuse yet. We will see...
Answer to: Why can I not get into my tablet the screen went blackThese tablets are plagued with this kind of problem, Can you remove the back cover and disconnect the battery? This may fix your problem.