Emergencies & HazardsCâu 87 / 120
Your air brakes fail on a downgrade and the low-pressure warning is on. What is your best course of action?
a.Downshift to use engine braking, look for an escape ramp or an uphill escape route, and use the parking brake or a soft-shoulder route as a last resort
b.Pump the brake pedal rapidly to rebuild pressure
c.Shift to neutral so the vehicle rolls more freely
d.Shut off the engine to stop the vehicle
Giải thích
Engine braking and an escape ramp are the reliable tools once the service brakes are gone, and speed must be controlled before it becomes uncontrollable. Pumping air brakes wastes remaining pressure, neutral increases speed, and shutting off the engine removes power steering and engine braking together.
Luyện miễn phí toàn bộ 120 câu hỏi — không cần đăng ký.
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