Yeah might be tedious work but hopefully it will help finding out which is the culprit and then the more important question why is it popping out.Yes, that's what I think: next time it happens I will first push down "interesting" fuses and relays one by one and try to start the motor after each "push down".
Would be nice if something like that is available for consumers or any other OBD tool on the private market but i guess we still have to wait.It would be good to get it plugged into the Ineos diagnostic tool and see if there's any fault codes relating to the immobiliser failing a handshake or something similar.
Maybe INEOS can beside the 3d workshop manuals also sell Diagnostics SW to read out the faults for not a too high price.
This should help with the help owners repair out in the bush