After searching the web and many other Z sites it seems that, ' on occasion' the radio in the early E85's that do not need a security code go into a state of complete hibernation of disablement. I have found many cases of the radio's going into disabled mode when batteries have been disconnected but not a single happy story of one being brought back to life. I remember, many years ago, buying a radio off a mate who had no code and putting it in the freezer for a week as that's what somebody told me to do,(probably the chap who sold it me) and no I do not remember the out come 
So hereth endeth the story and now to buy another radio.
So hereth endeth the story and now to buy another radio.