Vehicle InspectionQuestion 5 of 120
You are running the air-brake check with a fully charged system, engine off, and the service brakes released. What is the maximum allowable air pressure loss per minute for a combination vehicle?
a.2 psi per minute
b.3 psi per minute
c.4 psi per minute
d.6 psi per minute
Explanation
With brakes released, a combination vehicle may lose no more than 3 psi per minute; a single vehicle is limited to 2 psi per minute. With the brakes applied the limits rise to 3 psi for a single vehicle and 4 psi for a combination, and 6 psi per minute always indicates an unsafe leak.
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