Air Brake Practice Test

What action should a driver take if the air pressure gauge indicates low pressure?

1. Continue driving cautiously

2. Engage the emergency brake

3. Stop and investigate the issue

4. Increase throttle to build air pressure

The correct answer is: Stop and investigate the issue

When the air pressure gauge indicates low pressure, the appropriate action for a driver is to stop and investigate the issue. Low air pressure in the brake system can significantly reduce brake effectiveness and lead to brake failure. It is crucial to address any potential problems immediately to ensure safety on the road. Continuing to drive cautiously may not resolve the underlying problem and could lead to dangerous situations. Engaging the emergency brake could be an extreme measure, as it may not address the root cause of the low pressure and could cause the vehicle to become immobile. Increasing throttle to build air pressure is not a reliable solution since it does not guarantee that the air system will recover pressure effectively, and doing so could also be dangerous if brakes fail unexpectedly. Thus, stopping and investigating allows the driver to ensure that the air brake system is functioning correctly before proceeding.