I was driving about 25-30 mph and was coming up to an intersection, I tried braking when my brakes completely failed. They touched the floor with no resistance what so ever...I considered the emergency brake and started pumping the brake when just as suddenly the brakes were working again...this is a huge concern for me..when I brought it to the garage they could see nothing wrong with any of the brakes...how is this possible?? and what can be done?? I have driven cars with no brakes before but there was always something ,grinding etc. This was as if the brakes no longer existed. This is only a 3 year old vehicle and it has not been in any accidents and has been maintained, brakes and otherwise. I'm extremely concerned about the safety of my vehicle.