View instructions
The air brakes endorsement applies to applicants who wish to drive a vehicle with air brakes in Class A, B, or C CDL. To drive a vehicle with air brakes, you must pass the air brake component of the Idaho CDL knowledge test. The ID CDL air brakes test consists of 25 questions, and you'll need at least 20 correct answers to pass (80%). The test covers the information found in the air brakes section of the Idaho CDL Manual. Take this ID CDL practice test now to prepare for the actual air brakes test!
1. When driving at night, you should:
look directly at the lights of oncoming vehicles.
drive slowly enough to see obstacles with your headlights.
put your own high beams on if other drivers don't put their low beams on.
2. Passive railroad crossings:
have at least one traffic control device.
do not have traffic control devices.
should never be crossed using a CMV.
3. When going down a steep downgrade, you should:
use the parking brake.
avoid braking and rely on engine braking.
use a low gear, and a proper braking technique.
4. An alcohol evaporator is important during:
hot weather.
dry weather.
cold weather.
5. Which of the following is NOT a way to determine if your trailer is equipped with ABS (antilock braking system)?
It was built after March 1, 1998.
The letters "ABS" are printed on the side of the steering wheel.
It has yellow ABS malfunction lamps.
6. How can you tell if your vehicle is equipped with ABS (anti-lock braking system)?
There is no way to tell, ABS is still optional on all vehicle types.
Trucks, buses, trailers, and converter dollies built after 1998 are required to have ABS.
ABS is required on all vehicles manufactured on or after 2000.
7. If the ABS is not working:
you still have normal brake functions.
the vehicle will have weak brakes.
the vehicle will have no brakes.
8. Dual tires:
should not come in contact with each other.
should come in contact with each other whenever possible.
should always come in contact with each other.
9. To control your speed on a downgrade, you should:
use controlled braking.
fully apply the brakes.
use engine braking.
10. The safety valve is usually set to open at:
200 psi
150 psi
125 psi
Page 1 of 3
Next page

ID CDL Air Brakes Test

Number of questions: 25
Correct answers to pass:20
Passing score:80%
Share This Online CDL Test
Rate this CDL Air Brakes Test
4.8 out of 5
based on 283 votes