I tried pulling the battery for a while. I now have an incorrect clock and date. Surprising how you miss the settings options!
Despite the VCDS MOST test returning everything fine on both optical and electrical, on normal and -3db, I've bought a paid of terminators to the optical bus. ~£7 on ebay.
It seems a cheap and useful thing to knock things off the ring loop and IF it's the phone, I can just delete it. I've not used the phone in however many years of having the car and the old tesco sim that came with the car seems to have died anyway. I used it once to call my mobile to find it
I'm thinking, find the head unit in the glove box area and terminate there and see if i get the screen back!
For this weekend away I ordered a nice Soundcore motion+ and will borrow the GFs sat-nav. I'd take the PA painted jeep but it's a warm one and i'd like the nice aircon. Besides having a decent travel speaker for the cottage will be a bonus