This article refers to the ULF that BimmerNav supply with their ready made kits but the information is still relevant if you’re buying one to make with your own kit. The better (or later generation) you buy the more it costs …….. a lot more! I initially went for a fifth generation which worked fine but later found a reasonably priced 8th generation.
BimmerNav …. “A Very common question from the informed BMW owner is, “What BMW ULF module do you ship with your Bluetooth kit? This is actually the best question that you could ask a vendor of any BMW control modules including your local BMW dealer. The answer from us is the newest one that we can find worldwide, which is the The latest version available worldwide from BMW”.
The reason is as follows ……. https://store.bimmernav.com/blogs/installation/history-and-comparison-of-bmw-ulf-modules