Hey man, I am digging into this too. My dilemma:
Have heated seats but they are non zsp. Bought a zsp seat that was supposedly heated. Swapped them out and only the forward/back/down/up and recline works. No lumbar, no heat and no bolster support.
In looking at the zsp seat harness there are three main wires:
Then there are 9 other wires that are small and obviously NOT for supplying power. These are consistent for both harnesses.
Non zsp (heated) harness:
From this it is obvious to conclude that the harnesses are different (duh). I am assuming the brown power the forward/back/up/down and the reclining. I am figuring the lumbar and bolster support is the brown/red and they are on the same circuit. The red/white is probably for heating, but it is not on the new harness, soooooo... the question is whether the seat is heated or not. I will be doing a test this weekend with my wife's car which has zsp and is heated. I will take it out and then plug it in to my car, if I have heat with her's then I think it's obvious that at the very least the harness needs to be changed on this seat, but possible that these seats are not heated and I will need to put elements in.
Either way, I think this would be a great project to work on.
"Happiness is found in owning a BMW, bliss is is found in modifying the heck out of it!"