Brakes with automatic slack adjusters repeatedly fall out of adjustment. Which response addresses the concern described in the manual?
Correct answer: Have the underlying fault diagnosed and repaired
Repeated manual adjustment can mask a fault in an automatic adjuster or related components. The system needs qualified diagnosis using the manufacturer's service instructions, not a routine workaround.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-6, physical 77 > 5.3.2 During Step 5 Walk-around Inspection > Check Slack Adjusters on S-cam Brakes ↗
During the air-brake walk-around, a hose leading to a brake chamber is worn where it rubs another part. How should the finding be treated?
Correct answer: As a brake-system defect needing attention
The inspection specifically includes cut or rubbing-worn air hoses. A normal pressure reading at one moment does not make physical hose damage acceptable.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-6, physical 77 > 5.3.2 During Step 5 Walk-around Inspection > Check Brake Drums (or Discs), Linings, and Hoses ↗
A driver is checking the governor on a particular truck. What should determine the expected cut-in and cut-out pressures?
Correct answer: The manufacturer's specifications for that system
The manual gives approximate typical values but directs the driver to check the manufacturer's specifications. Treating a typical value as universal can misjudge the system.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-6, physical 77 > 5.3.3 Step 7 Final Air Brake Check > Check Air Compressor Governor Cut-in and Cut-out Pressures ↗
Two air-leakage observations were made: one with the foot brake released and one with it fully held down. Can their results simply be judged as the same test?
Correct answer: No; test conditions and vehicle configuration matter
The manual separates released-brake and applied-brake checks and distinguishes single from combination vehicles. A result must be matched to its actual setup; this item does not supply numerical limits or replace a complete test procedure.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-7, physical 78 > 5.3.3 Step 7 Final Air Brake Check > Test Air Leakage Rate (continued from printed 5-6) ↗
A dual-air truck has larger-than-minimum air reservoirs. Why consult its manufacturer's specifications when evaluating pressure buildup?
Correct answer: The larger tanks can take longer to fill without indicating a fault
The manual expressly allows that larger-than-minimum tanks may have a longer safe buildup time. It does not say that slow buildup can always be ignored.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-7, physical 78 > 5.3.3 Step 7 Final Air Brake Check > Check Rate of Air Pressure Buildup ↗
During a properly secured stationary low-pressure warning check, the engine is off and air pressure is being reduced as instructed. What electrical condition does the manual specify?
Correct answer: Electrical power is on
The warning check is performed with the engine off but electrical power on. This question isolates that condition; it is not the complete preparation or pressure-threshold procedure.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-7, physical 78 > 5.3.3 Step 7 Final Air Brake Check > Test Low Pressure Warning Signal ↗
The low-air warning activates while an air-braked truck is moving. What is the appropriate immediate plan?
Correct answer: Stop and safely park as soon as possible while control remains
The remaining air allows controlled braking only for a limited time. Stop safely before it is exhausted rather than waiting for automatic spring-brake application.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-9, physical 80 > 5.4.7 Low Air Pressure ↗
Why does planning a stop with air brakes include brake-lag distance in addition to perception, reaction, and braking distance?
Correct answer: Air takes time to travel through the system and apply the brakes
Brake lag is the system response time after pedal application. The manual includes it as an additional stopping-distance component; no universal time or distance is assumed here.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-8, physical 79 > 5.4.4 Stopping Distance ↗
A driver says that ABS guarantees a shorter stop on every road surface. What is the sound correction?
Correct answer: ABS helps prevent lockup but does not guarantee a shorter stop
ABS is intended to help maintain control by preventing wheel lockup. That benefit is not a promise of shorter stopping distance in every situation.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-4, physical 75 > 5.1.16 Antilock Braking Systems (ABS) ↗
An ABS malfunction is identified, but the vehicle's conventional brake system has no other fault. What does loss of ABS by itself mean?
Correct answer: Regular braking remains, but the ABS needs service
ABS is an addition to the regular brake system. Losing its assistance does not by itself eliminate regular braking; the malfunction still needs attention. This is not clearance to drive a vehicle with other brake defects.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-8, physical 79 > 5.4.2 Braking with Antilock Brakes ↗
A bus is equipped with the described separate emergency reservoir for releasing its spring brakes after main-air loss. What limits its use?
Correct answer: The reserve can release the brakes only a limited number of times
This optional arrangement provides only a limited reserve for emergency movement. It is not a universal bus feature or a repair of the failed main system.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-4, physical 75 > 5.1.15 Parking Brake Controls > Dual Parking Control Valves ↗
A vehicle has a dashboard modulating valve specifically for its spring brakes. What function distinguishes that control?
Correct answer: It allows the spring brakes to be applied gradually
On vehicles equipped with this feature, moving the lever changes the spring-brake application. The question identifies its function, not a universal emergency-braking maneuver.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-3, physical 74 > 5.1.15 Parking Brake Controls > Modulating Control Valves ↗
A truck's air compressor has its own oil supply rather than engine-oil lubrication. What additional check does the manual call for before driving?
Correct answer: Check the compressor's oil level
Some compressors have a separate oil supply, while others use engine oil. The inspection must match the actual compressor design.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-1, physical 72 > 5.1.1 Air Compressor ↗
How does the air-brake system described in the manual signal brake application to drivers behind?
Correct answer: Air pressure operates an electrical stop-light switch
A pressure-operated electrical switch turns on the brake lights during air-brake application. This is a component-function question, not a substitute for checking the lamps.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-3, physical 74 > 5.1.12 Stop Light Switch ↗
A parked vehicle has spring brakes applied and no reliable protection against compounding. Why avoid pressing its service-brake pedal at the same time?
Correct answer: Combined spring and air forces can damage the brakes
Some systems protect against combined application forces, but not all do and protection may fail. The manual advises avoiding the habit of pressing the service pedal while the spring brakes are applied.
Source: New Jersey CDL Manual, March 2025 cover; Section 5, July 2017 footer, printed 5-3, physical 74 > 5.1.15 Parking Brake Controls > Caution ↗
