This winter I had extensive work done to my braking system in both the front and rear of my 06 Colorado I5 Z71 4x4. New rear drums and shoes, new hubs with integrated abs sensors, front calipers and pads, new rotors up front. The only thing they didn't replace up front was the hoses. Today I stopped at AutoZone because my check engine light had come on and I suspected it was a bad gas cap but wanted to verify. The reader did show a bad or loose cap which I then replaced. The PROBLEM is that the code reader also threw a fault code for "right front wheel speed sensor AND left front wheel speed sensor!". I have no braking issues since the repairs and no dash light abs fault indication. I spent $2 K on that braking system and I'll be damned if I'm not going back to the repair shop! What are the possibilities for the code reader to indicate those faults? What could be wrong if all that was replaced and is brand new? Thanks for your advice!