InspectionQuestion 30 of 60
At what pressure should the spring brakes come on automatically during the continued-air-loss test?
a.Below 90 psi
b.Below 75 psi
c.Below 100 psi
d.In the range of about 20 to 45 psi
Explanation
Continuing to fan off the air, the spring brakes should come on automatically when tank pressure falls to the manufacturer's specified level, usually in the range of about 20 to 45 psi. On a tractor-trailer, you may hear the parking brake valve pop out. This confirms the automatic emergency braking works.
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