A magnetic sensor is placed on each wheel at a fixed distance to a toothed ring which is rotating with the wheel. The sensors can be changed but they should be installed at their articulated positions whereas the toothed rings can be changed too but this would demand disassembling of the hub or axle shaft. To remove and install, safely support and raise the vehicle, and then take out the wheel. Disconnect the connector, undo the mounting bolts / nuts and withdraw the sensor. In installation, undo the steps of removal, screw 12-16 ft. lbs. (16-22 Nm) sensor bolts tighter. When it comes to the Millenia, the first thing to do would be to unplug the electrical connector of the ABS speed sensor under the hood and then lift up and support the vehicle so as to get rid of the tire and wheel. Disconnect the ABS sensor wire bracket and the two nuts with the body, and then the two nuts connecting the two nuts to the speed sensor wire clamp. Take off the grommet and the speed sensor wire, located in the engine compartment, and remove the bolt that connects the speed sensor wire clamp with the knuckle as well as remove the ABS speed sensor. To install, attach the ABS speed sensor by screwing it to 14-18 ft. lbs. (19-25 Nm) with its mounting bolt and verify the clearance between the wheel speed sensor and the sensor rotor and ensure it is not exceeding 0.012-0.043 in. (0.3-1.1 mm). Otherwise, change the sensor rotor or sensor ABS sensor. Reconnect the speed sensor wire clamp to the steering knuckle and then feed the ABS speed sensor wire back into the engine compartment, re-fit the grommet, and fasten the wire clamps with the strut bracket and body bracket and tighten all the nuts to 70-95.4 in. lbs. (7.9-10.7 Nm). Lastly, replace the tire and wheel, lower the vehicle and reconnect the electrical connector of a speed sensor. To take off the rear, unplug the electrical connector of the speed sensor, remove the bolts holding the strut assembly and sensor wire clamps to the body, remove the mounting bolt of the sensor and remove the sensor. The procedures are reinstallation in the same order followed by mounting bolt and wire clamp mounting bolts tightened to 14-18 ft. lbs. (19-25 Nm).