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51% of Brake System Faults Linked to Air Brake Subsystem

A new analysis from Zonar explores thousands of reported brake system faults across the freight, passenger, and vocational transportation industries.

August 25, 2022
51% of Brake System Faults Linked to Air Brake Subsystem

Fleet operators must ensure their vehicles have safe brakes all year long — not just during Brake Safety Week.

Photo: pixabay.com

2 min to read


As more commercial vehicles hit the road, brake system faults have increased ten-fold, with air brake-related components representing 51% of all faults, according to new research from Zonar.

Moreover, some 66% of all-reported air brake-related faults are due to problems with the ABS system, the most faulty component of the air brake subsystem.

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The Commercial Vehicle Safety Alliance’s annual Brake Safety Week runs from Aug. 21-27.  The yearly commercial motor vehicle brake-safety inspection, enforcement, and education initiative spans the U.S., Canada, and Mexico. However, fleet operators should make sure their vehicles have safe brakes all year long.

Now is a good time to for operators to get a better understanding of the most typical brake errors.

To determine the most common brake system malfunctions, Zonar analyzed 20,788 brake system-related faults through its electronically verified inspection reporting solution, Zonar EVIR, from May 2021 to May 2022, across the freight, passenger, and vocational transportation industries.

Other braking subsystems that raked among the top five for reported faults include parking/emergency brakes which ranked second, representing 18% of all brake faults. The parking brake was the most faulty component of this subsystem, as it was reported in a staggering 98% of cases.

Wheel-end brake subsystems took third place for overall faults (16%), with brake drum malfunctions claiming the lion-share — 58% -- of this category. Ranking fourth on the overall list, 12% of faults were attributed to the hydraulic brake subsystem and the most faulty component of it appears to be the ABS system, which was reported in some 80% of all hydraulic brake-related faults.

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Finally, the universal/master brake subsystem took fifth place, representing 3% of all bx`rake malfunctions. Moreover, some 49% of all reported universal/master brake-related faults were linked to brake pedal problems.

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