Practice question

What happens to the braking system if the air compressor fails on an HGV?

  1. Nothing — the brakes work without air
  2. The air pressure drops and eventually the spring brakes automatically apply, stopping the vehicle
  3. The vehicle speeds up
  4. Only the trailer brakes are affected

Answer: B — The air pressure drops and eventually the spring brakes automatically apply, stopping the vehicle

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Practice more: UK LGV Theory Test (Driver CPC Part 1) →