The driver must be able to see a low air pressure warning which comes on before pressure in the service air tanks fall below ____ psi.
Answer: B
60
Regulations dictate that a visible low air pressure warning indicator be activated and placed in full view of the operator when the pressure in the air supply system falls lower than 75 to 55 psi.
All choices
- A80
- B60
- C40
Why the other answers are wrong
A. 80
Choice A is wrong because the low air pressure warning must activate below 75 to 55 psi, not as high as 80 psi.
C. 40
Choice C is wrong because the warning activates before pressure falls below 55 psi, not as low as 40 psi.
CDL Air Brakes Test Info
Questions on Exam
25
Passing Score
80%
Time Limit
Typically 30 minutes; varies by testing location
The Air Brakes test content is federally standardized, so this question applies in every state. Age limits, fees, and testing procedures do vary — check your state's CDL requirements.
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More CDL Air Brakes Practice Questions
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