Changing navigation headunit swap nbt evo

[Beemerm3]

Just posting this as it was hard to find on the internet. I recently had a failed headunit and replaced it with a used one on ebay. I swapped the same software and everything. Supposedly it works if the headunit is upgraded. But u could be wasting money if coding didnt work...I swapped it. It turned on for a day then says no signal. Had an independent shop code the headunit . Changed the Vin to mines and it works now. Eventually it would say no signal. But doesn't mean it doesn't work. It's just shut down. Saved myself 2100 (without coding) had I bought a new headunit.