I had this problem. Took it to Ciroen main dealers (bought car there 7 years ago).
They first cleaned the wheel sensor but no joy (free of charge whilst having annual service and MOT).
Then replaced the ABS Sensor - Joy of joys it worked a treat!
Cost me £150 including sensor. very pleased.
James7447
April 2013
could be a broken ABS ring
steve
November 2011
could be any number of things and a suitable code reader would be your best bet to help you out
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