System PartsQuestion 11 of 60
What is the purpose of the supply pressure gauge in the cab?
a.To show how much pressure is in the air tanks
b.To measure the vehicle's road speed
c.To display engine oil temperature
d.To count the number of brake applications
Explanation
The supply pressure gauge shows how much air pressure is in the storage tanks. Dual air systems usually have a gauge for each half of the system, or a single gauge with two needles. Watching this gauge helps the driver know the brakes have enough air to operate.
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Related questions on this topic
- What happens to the spring brakes when air pressure drops to a very low level (for example, 20 to 45 psi)?
- Why do heavy vehicles use a dual air brake system?
- In a dual air brake system, before driving you should let air pressure build to at least what level in both systems?
- What does the application pressure gauge show?
- What does the brake pedal (foot valve) do in an air brake system?
- What is the function of the brake chamber and pushrod?
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