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Practice quizzes / ASE S4 Brakes (School Bus) Practice Questions - ASE S4 - Brakes (School Bus) Certification Exam / Question 51529
Practice question

A hydro-boost power assist unit on a hydraulic-brake school bus obtains its assist energy from:

  1. Engine intake manifold vacuum
  2. Power steering pump hydraulic pressure
  3. Compressed air from the reservoir
  4. Electric motor only

Answer: B — Power steering pump hydraulic pressure

The correct answer is shown above. Try the full quiz for additional practice.

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