Any updates? I have been facing the same issue. took to dealer and asked them to check my 48V battery as I assumed this was the issue and covered under 5 year warranty. They said it was my 12V battery. So I replaced it with an Odessey battery in March. I am now having the same issue and I suspect it is tied to my e-Touque/48V system. But then again, if that was the case, it sure took a while for my new battery to drain and I would have thought my new battery would have drained sooner. I am going to start trouble shooting a parasitic drain but sure wish there was a way to test the 48V and know if it was charging ok.