During the trailer air brake check, pushing in the trailer air supply valve fails to release the trailer's brakes. What should you do?

Pick an answer

1. Do not drive the vehicle until the problem is found and fixed
2. Ignore it, since the tractor brakes still work
3. Drive carefully at reduced speed to the nearest shop instead of stopping
4. Tap the knob a few times and continue the trip

Correct!

Not quite. The correct answer is highlighted.