CDL Practice Tests

Combination Vehicles Test

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Question #1 of 52

Combination Vehicles Test Question Image

What is the purpose of the emergency air supply line?


This line carries air to the tractor air tanks and controls the service brakes on combination vehicles.

This line carries air to the trailer air tanks and controls the service brakes on combination vehicles.

This line carries air to the trailer air tanks and controls the emergency brakes on combination vehicles.

This line carries air to the tractor air tanks and controls the emergency brakes on combination vehicles.

None of the above.

 

CDL Practice Test (Home) | General Knowledge Test 1 (Learning)

General Knowledge Test 2 (Learning) | Air Brake Test 1 (Learning) | Air Brake Test 2 (Learning)

Combination Vehicles (Learning) | Hazardous Materials (Learning) | Doubles & Triples (Learning)

Tanker Test (Learning) | School Bus (Learning) | Passenger Vehicle (Learning)

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