When I begin to drive my suv the brakes will scrub and seem to fail. It does stop it feels like the brakes are not catching. After this happens there is no problem with them again until the next time I drive the vehicle. This happens intermittenly. It happened once after I went through a large water puddle. My ABS light comes on intermittently also. I took it in for repair and the mechanic said he could find nothing wrong with my brakes and of course when he drove it this did not happen.
Brakes scrub, fail intermittently when vehicle cold. ABS light on intermittently. on 2002 Chevrolet Tahoe
Really need to get the ABS code, that will be key. I am surprised that your mechanic did not access the code, as this is crucial information. I would find a shop that can deal with an ABS problem, which you seem to have.
Update - Took to my usual mechanic yesterday and they checked everything from front to back EXCEPT the ABS Sensor. He didn't have the right equipment to check the sensor. I am taking it to see the other guy this afternoon. Everything else checked out great.