1999 GMC Jimmy • 6 cylinder 4WD Automatic • 110,000 miles

I have a 1999 jimmy 4.3L 4x4. I had all the brakes and rotors replaced 4 months ago and now the ABS light comes on and activates at low speeds. Father in law driving it and went to park and it didn't stop, went right threw fence. Took it to mechanic who replaced the abs sensor and a brake line. Apparently now the brakes work but the front right wheel where the sensor was replaced reads that it is going 3 miles an hour even though you are stopped. It apparentely rectifies itself over 15 miles an hour. I'm scared the brakes are going to fail and someone is going to get hurt. Checked recalls on GMC but nothing for my year. Any help would be great.
July 7, 2011.

Is "ABS" light still on? If you unplug the ABS unit, does it drive & stop normally?

Jul 7, 2011.
When the abs unit fails, you have breakes. Your reason for not having brakes was the brake line broke and was repaired. You need a pro that has a scanner to scan the abs to see what is wrong with it causing the light to stay on. Sounds like either the sensor is bad or it's not getting a good read. It needs to be scanned to see what is casuing the problem. Your brakes are good to use though as long as the system is n good working/repaired order.

Jul 9, 2011.