Chosen Solution
Hello. So I got this problem with my macbook pro where the fans would go on full speed constantly and some processes like kernel_task would drain the cpu with workloads over 100%. I decided to format the mac and reinstall which took forever. So i did the apple hardware test which gave me error 4sns/1/c0000008: tp0p 124. Which as far as i learned from reading on the net means there is something wrong with a sensor involved with the DC board? I got a magsafe DC board from another mac that i can replace but is this really where the problem is? Ive already tried reseting SMC and PRAM and nothing happens.
Yes, PCH is the Platform Controller Hub. As to why you’re getting the error it could be liquid damage which all you need to do is clean the board and maybe just need to touch up some solder joints. For now lets see what is visible. Follow this IFIXIT guide: MacBook Pro 13" Unibody Late 2011 Logic Board Replacement take the board out and make a good inspection of both sides. If you see any burnt or stained areas or any corrosion take a good picture and post it here for us to see.
