Presuming the ABS doesn't actually work now? Is the dash light permenantly on? They should be plug and play, but I had an issue with mine where the bracket was orientated the wrong way resulting in the rectangular metal pickup on the sensor to be vertical rather than horizonal making it throw a wobbler. So I'd say give it a good check make sure they are all orientated correctly and are the same distances from the ring on the drive shaft. If they are it could well be a faulty sensor or a different fault.
all you need to do is bridge pins 1 & 4 on the OBD port with a paper clip and count the number of flashes - Long flashes are 10's and short flashes are 1's.
The OBD port is located under the dash, drivers side footwell. Then google the fault code no.