InspectionQuestion 29 of 60
How do you test the low-pressure warning signal?
a.By draining the tanks while driving
b.By pulling on the slack adjusters
c.By turning the electrical power on and fanning off air until the warning activates
d.By revving the engine to build pressure
Explanation
With the key on and enough air in the system, step on and off the brake pedal to reduce tank pressure (this is called fanning off the air). The low air pressure warning signal must come on before the pressure drops below 60 psi. If it does not, the warning is faulty and must be repaired.
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