Section 11M.1.2
11M.1.2 - Air Brake or Hydraulic Brake Check (based on type of brake system)
Air Brake Check (Air Brake Equipped Vehicles Only)
Description:
Procedures to be followed in inspecting air brake systems.
Why Inspect:
Air brake safety devices vary. This procedure is designed to make certain that safety devices are operating correctly as air pressure drops from "normal" to "low air'' conditions. Loss of air pressure will cause the emergency brakes to activate causing an abrupt and uncontrolled stop.
Inspection:
Failure to explain and demonstrate (perform) all four (4) parts of the air brake check correctly will result in an automatic failure of the CDL Vehicle Inspection test.
The proper procedures for inspecting the air brake system are as follows:
- Air Gauge and Governor Cutoff Check - Chock the wheels, start the vehicle and inspect that the air gauge is working and builds the air pressure to governor cutoff (approximately 120 to 140 psi) and identify the cutoff pressure for your vehicle.
- Air Leakage Rate Test - Shut off the engine, return the key to the "on" or "battery charge" position, release the parking brake (all vehicles), and the tractor protection valve (combination vehicle). Fully apply the foot brake. Once the air gauge is stabilized, hold the foot brake for one (1) minute. Inspect the air gauge to see if the air pressure drops more than three (3) pounds in one (1) minute (single vehicle or trailer without airbrakes) or four (4) pounds in one (1) minute (combination vehicle).
- Air Warning Device(s) Test - Without restarting the engine, make sure the key or electrical power is in the "on" or "battery charge" position. Begin fanning off the air pressure by applying and releasing the foot brake. The low air warning devices (buzzer, light, and flag) should activate before air pressure drops below 55 psi or level specified by the manufacturer. It is the applicant's responsibility to know the vehicle manufacturer's specifications.
- Emergency Brake(s) Test - Continue to fan off the air pressure. The parking brake (or emergency brake) valve should close (pop out) between 20 psi and 45 psi (no less than 20 psi and no more than 45 psi).
- On air operated trailers, the tractor protection valve and trailer parking brake (or emergency brake) valve should close (pop out) at the same time or prior to the valve for the truck and / or tractor and / or bus.
- You will need to identify the level specified by the manufacturer for the vehicle you are testing in. If the vehicle's valves are not designed to pop out, you will need to listen for the sound of air discharging from the air system, which indicates the parking (or emergency) brakes have been applied. If the vehicle is equipped with a backup air system, you will need to explain that there is a backup system and that the valve(s) will not pop out.
Note: You will need to explain the specific procedures specified by the manufacturer for the vehicle you are testing in. It is your responsibility to know and describe to the examiner the vehicle manufacturer's specifications for air systems.
OR
Hydraulic Brake Check (Hydraulic Brake Equipped Vehicles Only)
Description:
Procedure to be followed to inspect hydraulic brakes. Types of hydraulic brake systems and inspection procedures will vary.
Why Inspect:
Damaged hydraulic hoses, leaks in the braking system or low hydraulic fluid will result in a partial or total loss of the braking system that may result in increased stopping distances or a crash.
Inspection:
Failure to explain and demonstrate the hydraulic brake check correctly will result in an automatic failure of the CDL Vehicle Inspection test. This check is designed to see that the hydraulic brakes operate correctly. Use the following hydraulic brake check steps based on your vehicle's system specifications:
- Inspect that indicators and warning systems are functioning, as specified by the manufacturer, if equipped.
- With the transmission placed in "park", identify the normal height of the brake pedal and inspect brake pedal pressure [i.e., pump the brake pedal three (3) times, and then hold it down for five (5) seconds), or as specified by the manufacturer. The brake pedal should not move (depress) after initial application and should be firm and have a sufficient amount of reserve for brake pedal application.
- Inspect that the hydraulic power assist system(s), if equipped, are functioning, as specified by the manufacturer.
Note: Hydraulic brake systems vary. Your system may require the ignition to be in the "on" position and / or the engine running. You will need to explain and demonstrate to the examiner the procedures for your vehicle as specified by the manufacturer.
Passenger Entry and Lift
Description:
Bus door(s) used for normal entry or exit. Passenger lift used for wheelchair accessibility.
Why Inspect:
All passengers must be able to enter and exit safely.
Inspection:
- Inspect that entry door(s) are not damaged, operate smoothly and close securely from the inside.
- Inspect that handrails are secure and, if equipped, that the step light(s) are working.
- Inspect that the entry steps are clear, and the tread is not loose, or worn.
- If equipped with a passenger lift, inspect for leaking, damaged or missing parts, and explain how the lift should be inspected for correct operation.
- If equipped, lift must be fully retracted and latched securely.
Emergency Exits
Description:
Bus doors, roof hatches, or push-out windows used for emergency evacuation.
Why Inspect:
Emergency exits must be operable in order to provide an escape for passengers during a crash or emergency.
Inspection:
- Inspect that all emergency exits are labeled, not damaged, operate smoothly, and close securely from the inside. Demonstrate that at least one (1) emergency exit operates smoothly, closes securely, and is not damaged. Confirm that the exit and warnings work properly. Point out and describe how all other emergency exits operate.
- Inspect that release handles can be operated properly both from inside and outside the vehicle.
- With the key in the "on" or "charged" position, inspect that emergency exit warning devices are working.
Passenger Seating
Description:
Passenger vehicle seats and frames.
Why Inspect:
Seats must be safe for passengers to sit in.
Inspection:
- Inspect that there are no broken seat frames and inspect that seat frames are firmly attached to the floor.
- Inspect that seat cushions are attached securely to the seat frames.
Passenger Monitoring Devices
Description:
Mirrors and monitoring devices, such as cameras, for observing and monitoring passengers or students.
Why Inspect:
Internal (passenger) and external (fender, cross-over and other) mirrors or monitoring devices for seeing and observing passengers or students help the driver to safely observe and monitor passengers and / or students during driving, loading and unloading. Passenger and / or school bus vehicle drivers must be able to see boarding and discharging passengers and / or students.
Inspection:
- Inspect that all internal and external passenger mirrors and mirror brackets are not bent and are mounted securely with no missing parts.
- Inspect all internal and external passenger mirrors for proper adjustment and that they are clean.
- If equipped, inspect that passenger monitoring devices or cameras are clean and viewable from the inside and the video display is operable and adjusted for viewing.
- Inspect student crossover mirrors (school bus only).