Thanks for the reply VeeRsix The problem arose again the other day, checked the rad temp sensor and seemed to be functioning properly. I heard a small pop sound while driving yesterday, pulled over and took a look. Basically the fan control unit under the expansion bottle was wrecked, smoke and all sorts. The little plastic lid had come loose and melted into the fuses, that and a few coolant leaks ive had recently prob didnt help. Replaced unit and the two plugs that go into the bottom as they had welded themselves to it. Hopefully its sorted now