Nanocom has a forum that you can search for most of these exact answers to problems.
Bought the Nanocom and after a long hassle setup ... it consistently refuses to connect to the ECU and Hella Cruise Control ..
Nanocom user error if the CC works... or... your CC unit crapped out on you and is why the Nanocom doesn't connect to it.
This is what I do to access the Hella CC unit:
turn the ignition key to the second position,
press your CC button on the console,
insert the ODB plug for the Nanocom,
wait for it to power up,
click ahead until you reach the Hella CC Unit page,
search for CC trouble codes,
clear CC trouble codes,
now you are connected to the Hella CC unit via Nanocom.
... But if you have a DI and a DII you will have to buy TWO Nanocoms. One Nanocom will not work for both - and it should. Instead your DII will work on the RR P38 and some other obscure LR.
So you are therefore ... FORCED to buy another one .. if you own a DI and want to use the Nanocom for it.
The only legacy Land Rovers that are covered by Nanocom is the Disco 2, P38 and the Td5/PUMA Defenders so it can't be used on a Disco 1.
And as I said before ... They have a cumbersome download process I don't want deal with. I want to buy something and have it work. Not spend 4 hours figuring it out. I followed the directions and did everything correct. It will not connect to the ECU (error ECU communication error) or Sync the odometer to the BCU. It's not working correctly post brain transplant.
It's best to keep your Nanocom updated. What Firmware version do you have? The most recent out now is 1.35 beta II. Sometimes with an firmware update you'll have to choose "Overwrite Target Config" and then reinsert your codes to fix an issue.
As for the BCU/odometer swap on a D2...
IMPORTANT NOTE. If the BCU is replaced and the mileage value in the replacement is higher than the one shown in the Instrument pack, then using the Sync BCU to Odometer function will result in having the higher value mileage shown in the vehicle.
I have a Autel AL619 Autolink Engine/ABS/SRS. off Amazon. It is cheap and reads all engine codes, ABS and SRS codes and was cheap. I have a 03 D2 so I am sure it works just as well on newer rovers.
Reading and clearing codes is a lot different than changing ECU, BCU configurations like the Nanocom does. From my experience the cheaper Autel, iCarsoft, Vgate and Ancel were crap diagnostic testers for Land Rovers.
IMHO the Foxwell NT520 beats these 4 testers.