Practice question

What can cause spring (parking) brakes to apply unexpectedly while driving?

Driver pressing the foot valve too lightly
Air pressure dropping below the spring brake apply range (about 20-45 psi), often from a major leak
Cold weather
Slow traffic

Answer: B — Air pressure dropping below the spring brake apply range (about 20-45 psi), often from a major leak

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