WHILE DRIVING AT HIGHWAY SPEEDS IT BECAME NECESSARY TO TAKE EVASIVE MANEUVERS. WHEN I SLAMMED ON THE BRAKES I DID NOT FEEL THE ABS ENGAGE. I LOST CONTROL OF THE VEHICLE AND HIT A GUARDRAIL. WHEN THIS OCCURRED THE VEHICLE ROLLED FRONT OVER BACK AND THE AIRBAGS NEVER DEPLOYED. THIS CONCERNED ME. HOW CAN A VEHICLE ROLL OVER AND THE AIRBAGS NEVER DEPLOY?*AK