1992 Buick Lesabre traction control and antilock brake ligh

I recently purchased this car from a private individual for a very reasonable price in "as is" condition. The traction and anti lock brake lights come on after reaching a speed of ~15mph. I have bled the brakes as they seemed soft. I have checked for fuses, only the anti lock has a fuse that I have found. I have replaced the right front wheel bearing assy as it was very noisy, this came with a new speed sensor built in. After finishing all this up, I noticed a missing connection on the master cylinder and discovered a plug lying nearby. I connected it, and started driving over 15 and no lights! I pressed hard on the brakes (it was snowy road conditions) and the anti lock brakes pumped as they should. I went around a corner and lost traction a little, thus spinning a tire and the lights came back on. I double checked the connection and it's still good. I understand how the traction control works by applying braking action to the spinning wheel, thus forcing torque to the other wheel. I would like some ideas of where to begin looking. Note: The left wheel sensor has been checked for connection. I am sure there should be continuity, but my repair manual gives no assistance in that regard. That wheel produces no bearing noises.