It could quite easily just be a communication error between modules. Nothing harmful, but annoying. Granted this should still not occur, but nearly every car I've ever had a tester on has shown up some form of communication error registered at some point, unbeknown to the owner.Sorting itself out is never a solution. Unless you know what triggers a problem like heat, charging rate, driving style etc you cannot really have peace of mind by not doing anything. Just keep pushing VW to acknowledge the issue publicly and share the fix with all dealers.