iPhone stuck in a bootloop, and unflashable

[Kovi]

I recently got an iPhone 6 plus with a cracked screen from a friend that had upgraded to the S8. I replaced the screen with one off ebay, and the phone still displayed things correctly, it just got stuck in a bootloop. I've tried updating via iTunes, using iTunes' recovery from an existing backup, and restoring to factory default via iTunes. Those all failed with error code 4013. I dug a little deeper and found a program called 3uTools. I've tried using that to flash it with the latest update, that also failed with error code -2. That error code means that there is a hardware problem. So, do any of y'all have and troubleshooting steps I can take to help identify the problem? I'm stuck in my house for the next few days (Thanks Harvey), so I'd like to get this problem fixed.

[Droidbot]

have you tried recovery/dfu mode via iTunes

[Kovi]

9 minutes ago, Droidbot said:

have you tried recovery/dfu mode via iTunes

Yes, I have. When I try and update it, it says "Your iPhone can't be updated; you must restore it to factory settings. And  when I try to restore it, it prepares to restore, then fails with "An unknown error occurred (4013)"

[Droidbot]

2 minutes ago, Kovi said:

Yes, I have

When I try and update it, it says "Your iPhone can't be updated; you must restore it to factory settings. And  when I try to restore it, it prepares to restore, then fails with "An unknown error occurred (4013)"

tried the quickswitch method? 

 

dfu, then wait for the spinning circle, disconnect the cable, then wait 10 seconds and plug it back in

[Kovi]

10 minutes ago, Droidbot said:

tried the quickswitch method? 

 

dfu, then wait for the spinning circle, disconnect the cable, then wait 10 seconds and plug it back in

I can't get the phone to turn off in order to put it into DFU.