If the ABS light is on the ABS system is not working. The light means it disabled. I would think it would be the rear sensor which is a common failure. Here is a guide and diagrams (below) on how to test and then replace the sensor.
At the rear axle housing pull the wiring harness connector from the speed sensor.
Remove the speed sensor hold down bolt and remove the speed sensor from the rear axle housing.
Clean the rear axle housing mounting surface. Use care to prevent dirt from entering the rear axle housing.
Inspect and clean the magnetized sensor pole piece to make sure that it is free from loose metal particles which could cause erratic system operation. Inspect the speed sensor O-ring for damage and replace if necessary.
Lightly lubricate the speed sensor O-ring with motor oil, align the bolt hole, and install.
NOTE: Do not apply force to the plastic sensor connector. The sensor flange should slide to the mounting surface. This will make sure the air gap setting is between 0.127-1.143 mm (0.005-0.045 inches) .
Install the speed sensor hold-down bolt and tighten to 34-40 Nm (25-29 ft. lbs.) .
Push the connector on the speed sensor.
Please let us know what happens.
Saturday, June 8th, 2019 AT 4:32 PM