Technician A says that the only means of stopping an air brake equipped,semi-trailer combination is by actuating the service application circuit.Technician B says that unless the hold-off circuit is fully charged with air,a semi-combination rig cannot be moved.Who is correct?

Question

Quizplus · Accepted Answer

Technician B is correct because the hold-off circuit, also known as the spring brake circuit, must be fully charged with air to release the spring brakes and allow the vehicle to move. Technician A is incorrect because there are other means, such as the parking brake, to stop the vehicle.

Technician a Says That the Only Means of Stopping an Air