Just a follow-up to say that I soldered the broken ribbon cable (as best I could), carefully put it back together and still have the same problem.
It may be the soldering broke on reassembly, or it has another problem.
I've had enough of it, fortunately was a donation so nothing lost, and it's going in the bin.
I would like to give a BIG thankyou to all those who tried their best to help me out, it was very much appreciated.
This thread can now be closed - thanks.