Question The air compressor is connected to the: Answers Transmission. Engine. Radiator. Explanation The air compressor of an air brake system is connected to the engine through gears or a v-belt. The compressor may be air-cooled or cooled by the engine cooling system. Take a FREE Practice Test Now This questions appears in the following tests: Michigan Knowledge Test Class A , Wyoming Knowledge Test Class A , Connecticut Knowledge Test Class B , Kentucky Knowledge Test Class B , Ohio Knowledge Test Class B , Rhode Island Knowledge Test Class B , Maine Air Brakes , New Mexico Air Brakes ,