Colorado CDL Practice Test: Class A - Test 2 2026
Based on
2026 CO CDL Handbook
Instruction: When applying for this license, applicants must pass a 50-question test. And applicants must score 80% to pass the test. The following questions are based on the details provided in the CO CDL Handbook. Endorsements that may be used with a Class A CDL include Hazardous Materials, Passenger, Double and Triples, HazMat and Tanker, Air Brakes and School bus. If you need additional information, please contact your local DMV office. You can find your nearest DMV office at Colorado DMV locations.
3. What is the purpose of dummy coupler?
A
Dummy couplers have no purpose. This is a name for couplers that are no longer working.
B
Compress air.
C
Prevent water and dirt from entering into the coupler and air lines.
D
Protect the air hoses from rubbing together.