I haven't put it back on the bike yet but will when I get home.
The screen was completely black, even when out of the unit but now its crystal clear.
Actually I got this trick from Kevin at Fastline UK, he said he's done it on several units. Sometimes it fixes instantly, sometimes it needs a few heat cycles to go away.
They have a secondhand PGM there at Fastline with 27,000km's so I'm going to buy and have it sent to Doobers on Friday, with any luck I should have a fully functional MC28 by Monday!