Adventra Gremlins

Gday all, been a while since I've needed to call apon your wisdom, let alone tweak an engine.
So let me start, I traded my 2010 VE SS ute for a more family friendly 05 VZ LX8 Adventra.
After taking delivery noticed couple minor things.. Interior lights being a standout, and electric mirrors too not working, thought never mind I can fix that, but when I started investigating, it seems to me they're BCM managed, plugging in the lighting fuse (that was missing) well we have action.
But one action I wasn't up for, the dash cluster coming to life and spitting codes at me left right and centre.
So leaves me the question, anyone ever experienced this before?
Really want to iron out BCM issues before I begin tuning.

Till recently this was my main issue, being a luxury model, has park sensors, and copped a nudge from the rear, panels now repaired the rear park assist isn't working. I dug around today found the loom on the driver side disconnected, reconnected the 2x 8pin plugs colour matching, now hit reverse its only a dull hum from the buzzer. So what are your suspicions, dead sensor, unplugged sensor or severed loom?

Cheers in advance

Well today I ran some further old school diagnostics, it seems that there is a back feed in somewhere in the BCM when the ignition is off, but courtesy lamp circuit is active. I've singled out the relay and pilot circuits to be fine, right now I seem to have caught up to the BCM. It's a Holden 589 High end BCM manufactured by Arrow Australia. From what I have found so far is the switched power-in from the illumination relay arrives at X1 pin10
I'm ok at electrical but easily lost on a complex PCB such as this one.
Anyone got a circuit diagram or idea where to go from here I'm all ears and eyes
Cheers