South Dakota CDL — Air Brakes practice
South Dakota CDL — Air Brakes: Penalties & Licensing practice test
The point system, license suspension, provisional-license rules, insurance requirements, and other licensing basics.
Content reviewed against official driver handbooks · August 12, 2026
8 questions · pass with 6 correct. You get instant feedback and an explanation after every answer.
Study questions with answers
8 sample Penalties & Licensing questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.
Show all 8 questions with answers
1. You pass South Dakota's Air Brakes Test but put the rest of your licensing on hold. How long do a passed knowledge test and its fee stay valid?
Correct answer: 6 months
The manual says every passed knowledge test, along with the fee paid, remains valid for 6 months. Plan the skills test and the remaining steps inside that window.
Source: South Dakota Commercial Driver License Manual — General Information, Knowledge Tests
2. Which two codes on South Dakota's list of commercial driver license restrictions deal with air brakes?
Correct answer: L and Z
On South Dakota's restriction list, L means no air brakes and Z means no full air brakes (the driver tested with air over hydraulic brakes). E is no manual transmission, K is intrastate only, M and N limit passenger vehicles, O is a non-fifth-wheel CMV and V is a medical variance.
Source: South Dakota Commercial Driver License Manual — General Information, SD License Restrictions
3. How many questions are on South Dakota's Air Brakes knowledge test?
Correct answer: 25
South Dakota's list of CDL knowledge tests gives the Air Brakes Test 25 multiple-choice questions. The General Knowledge Test has 50, the Hazardous Materials Test has 30, and most of the other endorsement tests have 20.
Source: South Dakota Commercial Driver License Manual — General Information, Knowledge Tests
4. What score does South Dakota require to pass the Air Brakes Test, like every other CDL knowledge test?
Correct answer: 80% or better
The manual sets one passing mark for each CDL knowledge test: at least 80%. That applies to the 25-question Air Brakes Test just as it does to the General Knowledge Test.
Source: South Dakota Commercial Driver License Manual — General Information, Knowledge Tests
5. You fail South Dakota's Air Brakes Test at an exam station on a Tuesday morning. When is the earliest you can try again?
Correct answer: The next business day
South Dakota gives a knowledge test only once per day. To retest, the manual says you come back to an exam station on the following business day.
Source: South Dakota Commercial Driver License Manual — General Information, Knowledge Tests
6. You do not take the air brake part of the knowledge test, and South Dakota issues you a commercial learner's permit. Does the L restriction wait until you hold the full CDL?
Correct answer: No, the L restriction is marked on the CLP as well as on a CDL
The manual's description of the L restriction says an applicant who never takes the knowledge test's air brake portion, or does not pass it, gets the restriction on whichever document is issued, the CLP or the CDL. It bars driving a commercial vehicle that has air brakes of any type.
Source: South Dakota Commercial Driver License Manual — Section 1, Restrictions
7. An applicant asks to bring an interpreter to South Dakota's Air Brakes Test. What does the manual say?
Correct answer: Interpreters are not allowed on CDL knowledge tests
South Dakota does not permit an interpreter on any CDL knowledge test. The Air Brakes Test is one of those tests, so the rule covers it.
Source: South Dakota Commercial Driver License Manual — General Information, Knowledge Tests
8. On South Dakota's CDL Vehicle Inspection test, what happens if you do not correctly explain and demonstrate every part of the four-part air brake check?
Correct answer: You fail the Vehicle Inspection test automatically
Section 11 says that getting any of the four parts wrong means you automatically fail the CDL Vehicle Inspection test. The four parts are the air gauge and governor cutout check, the air leakage rate test, the air warning device test and the emergency brake test.
Source: South Dakota Commercial Driver License Manual — Section 11.1.2, Air Brake or Hydraulic Brake Check
More CDL — Air Brakes topics
Every South Dakota question is written from the official South Dakota driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free