Hi, I went through similar posts and I don't find a solution.
I have two 712 and they both behave the same: they do not display the same voltage as the multimeterS. I tested with two multimeters, both display the correct battery voltage.
I then proceeded to check the BMV + feed thinking this might be the fuse and v drop issue that was mentioned.
I disconnecting the v+ feed straight from the BMV and measured between it and the shunt I got the very same expected voltage as the + and - directly from the battery posts provide, eg no voltage drop!
That means the BMV displays a different voltage than two accurate voltmeters from exactly the same source feed/wires.
The drop is as follows:
Battery posts/BMV v+ feed voltage: 13.26v
BMV display, no bluethoot activated: 13.15v -> eg from BMV display only
BMV display WITH bluethoot activated: 13.02v -> reading from the app!
So there is an even greater drop when actually using VictronConnect and bluethoot!
That does not seem right at all!!!