Practice question

What is the function of the tractor protection valve in an articulated vehicle's air brake system?

It prevents the engine from overheating during heavy acceleration
It automatically seals the tractor's air brake system if the trailer breaks away or leaks
It regulates the charging current of the truck battery
It allows the driver to adjust the ride height of the tractor cabin

Answer: B — It automatically seals the tractor's air brake system if the trailer breaks away or leaks

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