Clive
I read your guide after doing my post, so I am going to try a factory reset when I get home tonight incase something has been turned off some where.
All I did was unpact, load batteries, test with OCF, swapping over on camera and remote, one had the focus assist working the other didn't. Put my original 622's on and no problems with either unit, so that elimated the camera and the flash, so it is definatly the individual unit thats not working.
Will update after factory reset tonight, and check on point 4 of your advice above,fingers crossed.