The issue occurs when first connecting. With the Candi it doesn’t see the candi and without it doesn’t connect to the vehicle correctly. After a couple tries it connects and all seems to work ok.
But I don’t trust it to not brick something on me someday.
It is your phrase "first connecting" that I was trying to pin down.
When you power up the Tech 2, there is no "connection" by which I mean that there has been zero communications between the Tech 2 and anything in the truck. If you select say Diagnostics, the select your year, vehicle type, powertrain, engine, transmission, Transfer case, Data Display (example), Engine Data Display,,,, up to this point there has been no communications attempted by the Tech 2 and the vehicle.
Only when you select, for example "Engine Data 1",, where the next screen normally flashes "waiting for data", only then are communications attempted.
Is this where you get the error(s).