System PartsQuestion 23 of 60
How are the service brakes applied in an air brake vehicle?
a.By pressing the brake pedal, which sends air to the brake chambers
b.By pulling the yellow parking brake knob
c.By turning off the engine
d.By draining the air tanks
Explanation
The service brakes are the normal driving brakes and are applied by pressing the brake pedal. Pressing the pedal sends air to the brake chambers, which move the pushrods and apply the brakes. Releasing the pedal lets the air out and releases the brakes.
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