Practice question

Why test trailer brakes with the hand valve but use the foot pedal for normal braking?

  1. The foot pedal applies all service brakes and reduces trailer-only skid risk
  2. The hand valve is stronger
  3. The foot pedal applies only parking brakes
  4. The hand valve is for parking

Answer: A — The foot pedal applies all service brakes and reduces trailer-only skid risk

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