How does the low air pressure warning threshold relate to the pressure at which spring brakes automatically apply?

Pick an answer

1. The warning activates at exactly the same pressure as spring brake application, leaving no advance notice at all
2. The warning activates only after the spring brakes have already applied
3. There is no defined relationship between the two pressures
4. The warning is set to activate at a higher pressure than the spring brake application point, giving the driver advance notice

Correct!

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