Forgot to update this. My car seems to be all good since I've had the control unit out from under the sterring wheel. I believe that one of the connections there were loose. Thanks everybody for all the advice.

Ross.

good to hear mate that its saughted I was going to recommend some one change the thread title to "the history of abs and how it effects modern day drivers"

I know it wasnt the cause but might be worth investing in something like a vagcom, you never know when these little gremlins will appear

Still got this problem... :(

This happened me twice about 6 months ago randomly, but went away when I restarted. Hasn't happened since. Strange