Arizona Air Brakes CDL Practice Test

What should be your first action when the low air pressure warning comes on?

1. Open the air supply control valve.

2. Adjust the brake pedal for more travel.

3. Stop and safely park as soon as possible.

4. Up-shift.

The correct answer is: Stop and safely park as soon as possible.

When the low air pressure warning comes on, the immediate priority is to ensure safety. This warning indicates that the air pressure in the brake system is falling to a level that could compromise braking effectiveness. The first action should be to stop and safely park the vehicle as soon as possible. Continuing to operate the vehicle with low air pressure puts both the driver and others on the road at risk because it can lead to brake failure or reduced braking capacity. Once safely parked, the driver can then assess the situation, such as checking for leaks or other mechanical issues, and determine the necessary steps to address the low air pressure situation. Safety is paramount, and taking prompt action in response to warnings is critical in maintaining control over the vehicle and ensuring the safety of everyone involved.