Traction control and ABS are sensed by the mono-pole sensors facing the speed rings on the front and rear wheels. It's those slotted little rings that create a 'frequency' when the bike is in motion telling the ECU how fast each wheel is rotating. If the sensor is too far from the ring it can't 'read' the gaps properly, too close, same problem. Since your bike is under warranty they should correct it no charge.
This is the front wheel of my Thruxton R (before spoke replacement with SS and wave rotors), you can see the 'speed ring' mounted to the brake disk:
The AFTER repairs the ABS light came on and I had to add a spacer to the sensor: