Had my aircon regassed, it was nearly bone dry apparently.
The garage also noted that my aircon button didn't seem to be working.
Appears that the blue LED control panel I got off eBay was a faulty one, probably a crossed solder from when they converted it.
I knew the aircon button activation light was at fault but thought the button was still working, apparently not so.
Luckily I still had my old one to hand so had to quickly swap them over just to make sure it was the controls crocked rather than the compressor or aircon clutch.
Thankfully it was the controls at fault, pity too much time has passed to complain to the seller.
May pass the dodgy one to my nieces boyfriend to look at as he's a control engineer and would likely make more sense of any fault than I would.