CDL · Emergencies

You are driving on flat ground in a vehicle with hydraulic brakes. When you step on the brake pedal, it sinks all the way to the floor. Which statement is correct?

Correct answer: Pumping the pedal may build up enough pressure to stop the vehicle.

Answer options

  1. AIf the transmission is automatic, you should not downshift
  2. BPumping the pedal may build up enough pressure to stop the vehicle Correct
  3. CThe parking brake is useless as well, because it runs on the same hydraulic system

Why

If a hydraulic brake pedal goes to the floor, pumping it a few times may restore enough pressure to stop, and you should downshift to help slow down with either a manual or an automatic transmission. The parking brake is independent of the hydraulic service brakes, so it remains available to help slow the vehicle.

About this question

Topic: Emergencies   License: CDL

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Where it applies: Asked in every state.

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This question is part of Emergency Maneuvers and Failures (14 questions). Take the full set and check your score.

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