The 2015 Macbook A1502 Retina is a fantastic Macbook, one of the last with removable storage and a full range of ports for connectivity as well as having the excellent retina resolution screen. Macbooks can often start to run very slow and many times this is caused by a sensor failure or the SMC itself being at fault. In this job the SMC has been damaged and we need to replace it. Traditionally you have to replace a like-for-like SMC when it comes to the board numbers (ie, 2015 A1502 can only use 2015 A1502 SMC) but thanks to the recent work by Muerto with his SMCFT project we can now utilise SMCs from a much wider selection of sources. https://github.com/MuertoGB/SMCFT