CA CDL Combination Vehicles Test
If you cannot make a turn without entering another traffic lane, you should: -
CORRECT ANSWER โโโ Turn wide as you complete the turn
You have pushed in the trailer supply valve. You should not move the tractor until
the whole air system is: - CORRECT ANSWER โโโ At normal pressure
Loss of air pressure in the emergency line causes: - CORRECT ANSWER โโโ The
trailer's emergency brakes to come on
To stop a trailer skid, you should: - CORRECT ANSWER โโโ Release the service
brakes
The air leakage rate for a combination of two vehicles (engine off, brakes off) should
not be greater than: - CORRECT ANSWER โโโ 3 psi or less in one minute
You are uncoupling a trailer. After you shut off the trailer air supply and lock the
trailer brakes, you should: - CORRECT ANSWER โโโ Back up gently to ease
pressure on the fifth wheel locking jaws
Before you back under a truck trailer, make sure the: - CORRECT ANSWER โโโ
Trailer brakes are locked
The tractor protection value will close and the trailer emergency brakes will come
on when there is a major leak in which brake line? - CORRECT ANSWER โโโ
Emergency brake line
To prevent a jackknife in normal driving, some drivers use the hand valve before
stopping on the brake pedal. Which of these statements is true? - CORRECT
ANSWER โโโ It should not be done
When you get ready to back under a trailer, you should line up: - CORRECT ANSWER
โโโ Directly in front of the trailer
You have a major leak in the service line and you put on the brakes. Service air
pressure will escape and cause the: - CORRECT ANSWER โโโ Trailer emergency
brakes to come on
After you lock the kingpin into the fifth wheel, you should check the connection by
pulling: - CORRECT ANSWER โโโ The tractor ahead gently with the trailer brakes
locked
After the trailer has been coupled to the tractor, the tractor protection control valve
should be placed in what position? - CORRECT ANSWER โโโ Normal position
One of the things a driver can do to prevent a rollover is to keep: - CORRECT
ANSWER โโโ The cargo as close to the ground as possible
What will happen if the air lines are crossed when you hook up to an old trailer with
no spring brakes? - CORRECT ANSWER โโโ You could drive away with no trailer
brakes
