The speed density conversion (MAF-less) is a service we offer to get rid of the MAF sensor on earlier 2.5 engines. For naturally aspirated and forced induction setups.
This is for 2005-2008 VW 2.5 running the Bosch ME7.1.1 ECU. The 2009+ does not have a MAF sensor from factory.
To simplify wiring, we re-use the wire the MAF used to provide the IAT signal to the ECU
You can validate the wiring/IAT signal by looking at the reported IAT value on live data (using the logger, VCDS, OBD11)