The integrated brake controller in my Silverado has a pressure sensor on the master cylinder to tell how hard I'm pressing the brake pedal. Unfortunately these things can fail (mine did) and the geniuses at GM decided that the brake controller shouldn't output anything if it doesn't know how hard I'm pressing - INCLUDING THE MANUAL CONTROL. So I'm rolling down the highway with a 20000lb toy hauler on the back with no brakes. What were they thinking? They did put a 'helpful' message on the DIC saying something like 'Check the brake system'.
