The ABS module on the 2012 GMC Sierra is faulty, but the shop that fixes the vehicle is certain that it is the root of the problem. In their tests, the module reported 3mph when the vehicle was still. They informed me that it was vital for the system to be able to identify zero in order for it to work. As a side note, I bike my abs virtually every day. I live on a gravel road, and driving through the spot where the gravel road meets the blacktop is like driving on ball bearings. So it must be repaired.
Thank you for reaching out. We do repair ABS control modules Here is the link https://www.upfix.com/product-category/repair-return/abs-modules-repair/