No, it's not under load - around 50-60 mph. Or could it be thermostat or temperature sensor? I will have to connect dongle again and check how it works while driving is it only on dash or is it for real.
Head gasket is rather impossible as engine was never overheated or so, plus low millage.

Small update pump 3 error is back from yesterday. So it looks like it's time to contact VW and ask what pump do i have or visit garage and ask them to check.