Try a DVSA HGV / LGV practice theory test question from the Braking Systems DVSA topic

What can coasting downhill seriously affect?

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Air-brake systems rely on an engine-driven compressor to keep the reservoir tanks at their operating pressure. Coasting downhill and relying on the brakes to control your speed could result in the loss of sufficient air pressure to operate the brakes effectively.

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This is DVSA HGV / LGV revision theory test question 1 of 104 from our free UK HGV / LGV practice theory test. This practice test follows the same format as the real DVSA multiple-choice HGV / LGV theory test.

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