This was a two part fix. The first part shows the initial test and diagnosis then dismantling down to the motherboard. It was a long long job. I'd never seen a first generation Microsoft Surface before other than in adverts so was totally unprepared for how to tackle this problem, but nothing ventured? Thankfully there are lots of videos on YouTube on how to take these beasties apart and teardowns too.
Here's one that I found particularly useful:
https://www.youtube.com/watch?v=Jqf2g...
and this one https://www.ifixit.com/Teardown/Micro...
I still don't know how to tell a 1st gen from the next iterations so if you have to work on one of these, I hope its the later generation as they appear to be infinitely easier to work on.
{youtube}https://www.youtube.com/watch?v=BnkIbfn_Tx0{/youtube)
In this second part, I replace the SSD and reinstall Windows, then test and finally reassemble. Sadly the touch screen facility failed to work after the repair, though it was recognised in device manager. But the customer was happy that it worked at all and they could use the touchpad or a mouse
{youtube}https://www.youtube.com/watch?v=w31yewJjZ14{/youtube}