I had thought about the reversing camera and side camera and think that will be my next stop. Had not considered the DVD player. I'll see if I can find somewhere to disconnect. Wonder if the rear stuff runs through the fuses at the back?
It’s about the only permanent live easily tapped into so any aftermarket accessories may be tapped into it. (As far as my limited understanding of circuit diagrams allows me to read them) as far as I can tell (from the not very comprehensive JPNZ Manual)
only the headunit runs on the BAT as opposed to ACC power.
Unfortunately the diagrams are copyrighted so you’d need to obtain your own Manual to satisfy yourself.
More food for thought. Only after market stuff I can find is a digital tuner which is disconnected and some kerb cameras. Maybe look there first. Anyone near Scotland have a workshop manual I could look at. Haha