Need to replace NAC with 2nd hand unit - recoding?

[Jules]

Hi

My NAC unit is going faulty. It first came up with the blue screen & "limited functionality" message. I reflashed it fine, but it lost it again the next day.

It continues to bug out, and often reflashes itself successfully if left on, but it will not hold for long, a day or so if really lucky. I just leave the USB in it permanently now as it flashes quicker from that.

So I guess I need a replacement unit.

If I buy a used one, will I be able to fit it and will it need recoding to my car? Will I need the donor car's VIN or anything like that?

I'm presuming it's not as simple as popping it into my car, starting up and reflashing it with the USB....

Part: 9820469280
NAC EUR wave2
VIN: VF7**************[VIN obfuscated, can be read by forum staff]

Thank you

Julian
PS: Is there a difference between B4DAB_DMT and B2DAB_DMT marked units?

[mickthemaverick]

I believe you do have to tell the BSI the new unit's code but there are far more knowlegeable members who will confirm for you.