Chosen Solution
Replaced the SSD in this system and been using it for a couple of weeks with no issue but now fans spin at full speed and laptop is very slow! Running Apple Hardware test I get this error: 4SNS/C0000008:Ts0P–124 After a little investigation I found this is a sensor found in the trackpad so I replaced the trackpad and trackpad flex cable with a known working one, however the system still runs at max fan speed and displays this error. Have also tried PRAM and SMC reset and nothing happens!
Well the error Ts0P is the top case error as you can see here directly from the Apple service manual
The sensor its self sits on the trackpad so you don’t need to go to Apples extreme of replacing the whole top case, just replace the trackpad. If that fails to solve the problem then you have a deeper problem within the logiboards SMC Logic on the back side often damaged by a spill
@toumbi Ts0P could be: Trackpad Trackpad Flex Camera (in some models) Trackpad flex connector (logic board) Since you already replaced the trackpad and the and the trackpad cable but ( on some models) there is a relationship between this sensor and the camera, try powering it up without the camera connected and see if that makes a difference. After that you need to check around the logic board connector and will have to do a deep dive onto the components related to the trackpad. For that you require the boardview as well as a multimeter etc.
