I have D5300 with the same metering malfunction error after I dropped. I tried couple of things, it won't work. I opened the back cover and found that the cable right by the view finder (on left - a big ribbon cable that spitted to smaller cable) came off. I put that back and fixed the issue. I put the picture in case others may benefit out of this. You will find full tear down video here which is helpful for disassembling. https://www.youtube.com/watch?v=l-ndgMs-5oI&t=94s