CDL Combination Vehicles TestDriving Combination Vehicles SafelyMedium
A commercial driver is operating a combination vehicle on a wet road and needs to make an emergency stop. The vehicle is equipped with ABS. What is the correct braking technique?
- APump the brakes rapidly to prevent wheel lock-up.
- BApply firm, steady pressure to the brake pedal without releasing until stopped.
- CApply light brake pressure, then gradually increase as the vehicle slows.
- DEngage the parking brake slightly to assist with stopping power.
Show answer & explanationAnswer & explanation
Correct answer: B. Apply firm, steady pressure to the brake pedal without releasing until stopped.
With ABS, the correct technique for an emergency stop is to apply firm, steady pressure to the brake pedal. The ABS system will automatically modulate braking to prevent wheel lock-up, allowing the driver to maintain steering control.
Why the other options are wrong
- A. Pumping the brakes is for vehicles without ABS; it interferes with ABS operation.
- C. Light, gradual braking is not appropriate for an emergency stop and will increase stopping distance.
- D. Engaging the parking brake while moving can cause a loss of control, especially in an emergency, as it typically only applies to the drive wheels or trailer.
ABS Emergency Braking
When a combination vehicle with ABS needs an emergency stop, apply firm, continuous pressure to the brake pedal; the ABS system will manage wheel lock-up.
- Do not pump the brakes with ABS.
- ABS helps maintain steering control.
- Apply firm, steady pressure.
Memory trick: ABS: Stomp, stay, steer.