Is it definitely the controller? Good way to test is 1) clear faults and turn ignition off 2) lift rear seats, you will see a couple of cables going to rear wheel wells and the connectors around the middle, these will be the ABS sensors 3) swap them over 4) turn on ignition and check vcds for errors, if the same sensor is showing as faulty it's likely the controller (as you just swapped them) It is possible to remove controller only but you need to be careful of bending and breaking the brake lines. Once off send to BBA reman, mine lasted for 4+ years and should still be going as Dave cw now