# Free Idaho CDL Air Brakes Practice Test 2023

Do you need an Idaho Air Brakes endorsement or an L endorsement for your commercial driving license? The Idaho CDL Air Brake test has some differences from other endorsements because your license will receive a mark of restriction if you fail the test. So having good preparation before exam day is very necessary. To ensure that our questions are relevant, all of our CDL practice test packs are based on the Idaho CDL manual. Each question has a detailed explanation for you to thoroughly learn the format and the topic. Don't be afraid of having a restriction on your license. Let’s try our Idaho CDL practice test to get ready to pass the Idaho CDL Air Brake Test now.

Our CDL practice tests:
Based on 2021 ID commercial driver's license manual
Perfect for first-time, renewal applicants
ID CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
The most common type of foundation brakes are:
2.
The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like:
3.
An air compressor can be cooled by _______.
4.
When is it OK to leave your truck unattended without applying the parking brakes and choking the wheels?
5.
If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?
6.
A mechanical device that drops a low air warning into a drivers view is called a:
7.
Why drain water from compressed air tanks?
8.
Excessive heat caused by using your brakes too often can also cause:
9.
Where is the modulating control valve located on some vehicles?
10.
When the air system is low ________.
11.
Another name for the brake pedal is the "foot valve", or:
12.
Some vehicles are equipped with a control allowing you to apply the spring brakes gradually, called a:
13.
"Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the proper level of alcohol?"
14.
If your truck has a dual air brake system, and one of the systems is low on pressure:
15.
All of the following are factors in total stopping distance except:
16.
Compared to hydraulic brakes, air brakes add how much distance to an average 55 mph stop?
17.
All of the following apply if the low air pressure warning signal does not work except:
18.
You should avoid using the parking brake when _______.
19.
Controlled braking is only possible _________.
20.
The air tanks must be drained because:
21.
Initial air leakage rate for combination vehicles should be:
22.
On newer vehicles, the parking brake control knob is typically yellow, but on older vehicles, the parking brake might be what color?
23.
The safety valve in the air compressor tank is set to open at _____.
24.
Vehicles without automatic air tank drains need to be checked manually to remove ________?
25.
What is an alternative name for a brake pedal?