CDL Combination Vehicles Practice Test Results

Question 1
90% answer correctly
How would a driver supply air to trailer air tanks?
Activate the service line
Pull out the trailer air supply valve
Push in the trailer air supply valve
Activate the air generator
Question 2
92% answer correctly
On a combination vehicle what color is the emergency air line?
White
Black
Red
Yellow
Question 3
53% answer correctly
What function does the service line perform?
Marks the maximum refill point for air tanks
Carries air controlled by the footbrake or trailer handbrake
Supplies air to the footbrake and trailer handbrake
Distributes air throughout the cab and to each of the trailers