dudu-lai Thank you for replying.
I connected the CANBUS like this:

On G3, I'm reading 0volts with the dudu plugged in or not plugged in,
on G2 I'm reading 0.02v plugged in and 1.3v not plugged in.
I only plugged in the power connector, the harness I have has 3 different connectors and I haven't figured out which is right yet, but I assumed it would power on without that at the moment.