Heavy trucks use a different protocol. Cars use 4 different protocols and the VCI can convert those 4 protocols to rs232 (rs232 is what PC`s read). Trucks use two protocols,J1939 and J1708. You need a VCI that can convert J1708 and J1939 over to rs232 so the software on your tablet can talk to the truck. As far as I know, the VCI that comes with MaxiSys only converts the 4 automotive protocols.
I heard Autel makes a heavy truck tool but I never seen one and they do not list it on their site.
Autel gives out OBD I connectors with their tools and they have no OBD I coverage so just because you have a connector don`t mean you have coverage with this company.
Kevin