Combination #1
Combination Vehicles Practice Test | Colorado 2025 #1 Page 2 of 3
Train for FREE online with our Colorado CDL combination vehicle test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a CO combination license in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that DMV requirements for issuing a combination license may vary from state to state.
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8 . To test the trailer service brakes, you should:
Move the vehicle forward slowly and apply the brakes with the hand control.
To test the trailer service brakes, you should first ensure that the braking system has a normal air pressure level, then release the parking brake. You should then move the vehicle forward slowly and apply the brakes with the hand control. If the trailer service brakes are working properly, you will feel the brakes activate.
9 . If unsure if a trailer is equipped with ABS, you can:
Remove a tire and look for the ABS sensor on the axle.
Trailers and converter dollies built on or after March 1, 1998 are required to have Anti-Lock Braking Systems (ABS). This will be indicated by the presence of a yellow malfunction lamp. You can determine if older trailers have ABS by checking under the trailers for ECU and wheel speed sensor wires coming from the back of the brakes.
10 . An Anti-Lock Braking System (ABS):
Assists with the operation of brake lights.
The function of an Anti-Lock Braking System (ABS) is to prevent a vehicle's wheels from locking up during hard braking.
11 . To prevent a rollover, a driver should:
Turn quickly.
Rollovers can happen when a combination vehicle is turned too quickly. To help prevent the risk of rollover, it is important to keep the vehicle's center of gravity low by loading cargo as close to the ground as possible.
12 . Compared to other commercial motor vehicles, combination vehicles need more space on the road because they are longer and they:
Swerve more often.
Combination vehicles need more space on the road than other commercial vehicles because they are longer and need more space to turn and stop. It is especially important to properly manage space when you are operating a combination vehicle.
13 . If you need to back your trailer but cannot back up in a straight path, you should:
Always turn to your right.
If you need to back your trailer but cannot back up in a straight path, you should back on a curved path toward the driver's side of the vehicle. This will permit you the best possible visibility while backing.
14 . Trailers with low underneath clearance may be difficult to drive:
At the posted speed limit.