I just took the vehicle out on the road. engaged the Cruise control. The Cruise light came on but again the vehicle just did not keep the speed. I then hit the brake peddle and the cruise light went off as it should. That tells me the switch on the master cylinder is working. The Off button and the On button on the wheel seem to work while the three on the right side don't. RESUME, SET SPEED, COAST. While doing the Seft Test Diagnostic thos three button gave no response while OFF AND ON did blink the "cruise light" once. Still at a loss......thanks for the response.