Broadway Vehicle battery not charging on EHU

I'd never seen that documented before, but I can confirm that the light stays on for the battery select switch (indicating the vehicle battery is selected) in the circumstances you describe, even though the panel is off. What I don't know is whether that actually results in the vehicle battery being the one charged. I don't know, because I've never checked!

On mine (which is a Celex, not an A/S model) you don't even need to start the engine - just turning the ignition on and off again will trigger the disabling of the panel, leaving the battery select unchanged.

If it warms up a bit later today, I'll maybe go out and check what it actually does.

Having said that, I don't ~think~ the background drain when the panel is on is anything like as high as with the later controllers. From memory, I think it's a few tens of milliamps, while with a EC500 or EC700 it is a lot higher (maybe ten times higher?).