What can cause air brake failure?

Answer: B — Insufficient air pressure in the system

Air brake failure can indeed be caused by insufficient air pressure in the system. Air brake systems rely on compressed air to operate effectively; without adequate pressure, the brakes cannot engage properly. This reduced pressure can lead to ineffective braking performance and an increased stopping distance, which poses a significant safety risk while driving. Proper maintenance of the air compressor, ensuring no leaks in the system, and regularly checking that the air pressure meets operational standards are essential practices to prevent this issue. Inadequate brake fluid levels are not a concern for air brakes, as they operate solely on air. The excessive use of brake linings pertains more to friction braking systems rather than air brakes, which do not rely on lining wear for their primary function. Frequent tire rotations, while an important aspect of vehicle maintenance, do not have a direct impact on air brake functionality.