My Roadster has been in storage mode for a couple of months, nicely holding to 30 mi range by charging automatically for a few minutes every day. All was well until today when the VDS showed this: The EVSE used is the Clipper Creek HCS-40 which is a reliable workhorse which shows a green light, no fault. Used with Henry's reliable Can JR. After changing to the Tesla UMC, the message still appears. The message also still appears after changing the charge mode to Standard. It seems to charge OK despite the message (my buddy who is my Roadster-minder let it charge in Standard mode for a few minutes back up to 32 mi range and then switched it back to Storage mode). Does anyone know what this message is all about? The only thing I could find on the forum about "Backup Power Supply" referred to the 12V battery - which to the best of my knowledge is not present in the 1.5s (mine is #243). If the message persists I am going to just change the charge mode to Standard and fill 'er up in order to have some SOC buffer in case this develops into a failure to charge. I'll be back home in a month so a Standard charge would last until I'm home to deal with it. Bottom line: Can any of you pros tell me about the "Backup Power Supply" on a Roadster 1.5 and shed light on the significance of this message?- Many thanks!