A combination vehicle's air system has been built up to governor cut-out. With the engine shut off and the brake pedal fully applied, the air pressure should drop by less than:

Answer options

Why

With the brakes held on and the engine off, a combination vehicle should lose less than 4 psi per minute after the first pressure drop, while a single vehicle should lose less than 3 psi. A faster loss points to a leak that must be fixed before you drive.

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.

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

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