You test a combination vehicle's air system with the engine off and the brakes applied. The pressure loss should be less than:

Answer options

Why

In this brakes-applied test, a combination vehicle may lose less than 4 psi each minute; the brakes-released limit is lower, at 3 psi. A quicker pressure drop points to a leak that needs fixing before the trip.

About this question

Topic: Air brakes   License: CDL

Part of these practice sets:

• Checking and Using Air Brakes

Where it applies: Asked in every state.

Practice the whole set

This question is part of Checking and Using Air Brakes (15 questions). Take the full set and check your score.

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