Practice question

In air brake-equipped vehicles, what does the low pressure warning signal indicate, and at what pressure should it activate?

It indicates high fuel level; activates at 120 psi
It indicates that reservoir pressure is dropping below a safe level; activates at around 60 psi
It indicates moisture in the air lines; activates at 90 psi
It indicates trailer uncoupling; activates at 30 psi

Answer: B — It indicates that reservoir pressure is dropping below a safe level; activates at around 60 psi

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