After a bit of research my code reader will only see engine faults. Need something like an Autel or budget alternative to see the other codes with all the other ECU’s and CANBUS. long term it’d be a good purchase but can’t source new in time for the MOT from AliExpress.

Fingers crossed it stays off for the MOT. Don't know if you managed to remove the terminals, if not here's a link that you may find uselful: -

https://www.rrsport.co.uk/gallery/albums/u...RATION.pdf

It's from the L405, but still spplicable

Cheers checked out of a lot of YouTube on de-pinning. I’m going for that and the white vinegar with one of the kids fine paintbrushes (then hairdryer). It’s not on at the start of a journey comng on after a few minutes suggesting to my mind a moody connection

Certainly worth a try, ideally you need a code, but worth a try none the less, perhaps try a bit of the Mrs nail varnish remover in case there is any oxidation on the contacts, shouldn't be as they are gold plated, but won't do any harm.

Crunch time for MOT loomed and without a decent code reader opted for a well trusted auto electrician who came up trumps. Turned out the issue was faulty continuity through the drivers seat connector. After splicing out the connector, soldering, shrink wrap and wrapping I’m code free at last.
A note to others really explore each seats connectors which I didn’t

So basically, right fix, wrong seat!! I did think it odd it was the passenger seat you were focusing on, as it's normally the drivers seat that gets most movement. On the plus side, you know the passenger seat will never play up now

Yes sort of barking up the wrong tree or seat in this case! With my man maths the fix (£65)was ultimately cheaper than most budget scanners (still getting a launch 123e though)
Nice to have no lights on… hopefully for a significant period