So sounds like it is Google Account locked. Also known as FRP (Factory Reset Protection). Obviously the easiest way to do that would be to try and remember the Google account that was used on the device, if you cannot remember the email you can go to https://accounts.google.com/signin/v2/us... where you should be able to find out your Gmail email if you put in either a phone number or another email associated with that account. Failing that there are plenty of ways to get past this if you just search the model number followed by FRP bypass on Google as long as you are the owner of the device.
Hi, A quick Google of the machine you say you use shows it just to be a heated flat plate, so do you use wire to remove polarizer? I use a dedicated Polarizer removal machine (Particularly the OCAMaster OM-C2) which I have used for hundreds of iPhone 7 LCD’s with basically zero broken. I also suggest using a mould to keep the flex in its natural folded position during every stage of refurbishment as these are very fragile and will often cause No touch or lines in the LCD if bent past 90 degrees. Hope this Helps.
Could be various things that cause it to not turn on, but the most likely cause will be a blown fuse. Will have to check for your specific car where the fuse is located for the stereo. There is also a fuse on the rear of the stereo itself on some models so this may be worth a look. Other than that it could simply be a faulty stereo or loose wiring at the back of it. The easiest way to check a fuse without the proper equipment it to pull it out an visually check if you can see a break in the wire in the plastic part between the 2 metal prongs.
Not sure if solved yet, but I had this exact issue, phone will bootloop, but when sensor flex is disconnected it will boot up fine. Strangely enough this was due to a small tear in the flex cable that connects the home button to the board. And when this cable is disconnected the phone boots fine even with sensor flex connected. Hope this helps