UK Car Repair Questions? Ask a Mechanic for Answers ASAP
can I ask did you replace the sensor on the corner with the broken ABS ring?
as its quite common for the broken ring to then clout the sensor and damage it
you can check each sensor's function by plugging the two output wires into an AC voltmeter and spinning the wheel quite quickly, you should get a voltage signal that increases with rev's.
Its possible that the fault is only a bad connection to one of the wheel sensors.
This may be remedied by removing each wheel in turn and unplugging each sensor and cleaning the contacts with a squirt of electrical contact cleaner. Then refitting.