So, I have found a couple of things that may happen. I have had verrrry small rock’s or flakes of metal bridge between two pins on a keyboard connector and cause it to be all wonky and not work with certain keys. The other thing that could have gone wrong would be that the keyboard needs to be replaced entirely. I would check and make sure the connector is clean and try to re-connect it first.
Hey there Logan. I would recommend doing what Mayer said above and reseat the display cable. if that doesn’t work you could replace the Display. It isn’t too terribly difficult of a job if you know your way around electronics and repairing them. Just watch a couple of videos and you should be perfectly fine!
With Apple computers, if the battery is bad or not recognized the computer will be very slow. so that is normal. Unfortunately, I have had my fair share of bad batteries from iFixit. They have a great return policy so you won’t have to dispute it with your bank. just let them know your issue with the battery and they will either refund you or send you a new one. With Apple computers, it should recognize the battery right away when you plug a new one in without having to do any reprogramming. So being that it doesn’t recognize it. It sounds like there is either something wrong with the battery or the main logic board. but it’s more likely to have an issue with the battery.
With these models this can sometimes be caused by either a faulty LCD Cable or a faulty LCD. It runs from the LCD to the Logic board. I would recommend if you can and have the knowledge to replace it yourself or take it to a reputable repair shop for help with it. This sounds to be a hardware issue more so than a software issue unfortunatly
Are you able to put in your old HD and Boot into it? Your Computer model is very notorious for having a bad GPU. Unfortunately there is not an easy fix for this without the use of Soldering or a replacement Motherboard. However, you would be running into the issue of the same problem happening again. Personally I would recommend looking into a replacement machine as the cost of repair for this computer vs. the value of it doesn’t make it worth the repair.