Hello, my question is, are tcu modules "plug and play"? Can U exchange them in car as U wish? Seems unlikely. https://static.nhtsa.gov/odi/tsbs/2018/MC-10152513-9999.pdf was the procedure to swap out the 2G TCU in '11 to '15 Leafs for a 3G-capable one. And now, the 3G version doesn't work...