Vehicle InspectionPregunta 4 de 120
At what air pressure must the low-air-pressure warning device on an air-brake vehicle come on?
a.At or below 45 psi
b.At or below 60 psi
c.At or below 85 psi
d.At or below 20 psi
Explicación
The low-pressure warning light and buzzer must activate at or before pressure drops to 60 psi, giving the driver time to stop while service brakes still work. Around 85 psi is a typical governor cut-in point, and 20 to 45 psi is the range in which spring brakes apply automatically, which is far too late for a warning.
Referencia Legal: 49 CFR §393.51Practica las 120 preguntas gratis — sin registro.
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