So my battery is A-OK, my problem was that I accidentally left the bluetooth dongle connected and it obviously drained the battery 🤦♂️ Anyway, all fine after a charge.
The setting under lights was there and disabled, so with great excitement I enabled the option and.... nothing. No difference
Thanks for the tips Run Buh, I'll try looking at those and as you say, won't just copy verbatim. Thanks too for the warning for the headlight settings, but sorry you took the pain. I was actually looking at those settings as they seemed inclined to be related, so glad I didn't touch them in the end.