CDL Combination Vehicles TestCombination Vehicle Air BrakesMedium
You are driving a combination vehicle equipped with ABS. You encounter an unexpected obstacle and must brake hard. How should you react to the ABS system during emergency braking?
- APump the brake pedal rapidly to help the ABS system work more effectively.
- BSteer aggressively to avoid the obstacle, letting ABS handle the braking.
- CApply constant, firm pressure to the brake pedal and steer normally.
- DRelease the brake pedal if you feel it pulsating or hear unusual noises.
Show answer & explanationAnswer & explanation
Correct answer: C. Apply constant, firm pressure to the brake pedal and steer normally.
With ABS, the correct technique for emergency braking is to apply firm, constant pressure to the brake pedal. The ABS system will automatically modulate the brake pressure to prevent wheel lock-up, allowing you to maintain steering control. Pumping the brakes overrides the ABS function and reduces its effectiveness.
Why the other options are wrong
- A. Pumping the brakes is incorrect for ABS; it interferes with the system's ability to maintain traction.
- B. While steering is crucial, 'aggressively' might be too much; the focus is on maintaining control while braking firmly.
- D. Pulsating or noise is normal ABS operation; releasing the pedal reduces braking effectiveness.
ABS Emergency Braking
The proper technique for emergency braking in a vehicle equipped with an Anti-lock Braking System (ABS), which involves applying constant, firm pressure to the brake pedal and steering to maintain control.
- Do NOT pump the brakes.
- Apply firm, constant pressure.
- Steer to avoid obstacles.
- Pulsation/noise is normal ABS operation.
Memory trick: ABS: Always Brake Steady, Steer Smart.