Practice question

A trailer service brake test fails after coupling. What should the driver suspect?

A normal condition until highway speed
A line, glad hand, valve, or brake-system fault that must be fixed before driving
A fifth wheel lubrication issue only
A cargo door problem only

Answer: B — A line, glad hand, valve, or brake-system fault that must be fixed before driving

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