Rear Camera and torch not working

Hi, I’ve recently been fixing up my old iphone 7 which has been broken for the last year with a smashed screen.. Ive since replaced the screen so everything is now functioning as it should, except for the rear facing camera and torch. I’ve put the rear camera into another iphone 7 to test it, and it was functioning as it should. So im just wondering what else would stop a rear camera and torch from working? Is there any ground screws or antennas that are missing? Or could it be board level damage. I’ve noticed that the logic board will heat up right over where the power ic is (I think so anyway, its the bit of the logic board with the tape over it below the rear camera) when I try to use my rear camera. Once i switch to my front facing camera it’ll cool down…

Thanks for reading and any suggestions are appreciated