What should be done if the air gauge does not rise to the normal operating pressure?

If the air gauge does not rise to the normal operating pressure, investigating the compressor and checking for any blockages is crucial because the compressor is responsible for building air pressure in the system. A malfunctioning compressor or a blockage can prevent adequate air supply, leading to insufficient pressure readings. This step is vital in diagnosing and addressing potential issues before operating the vehicle, ensuring safety and reliability.

Addressing the other options, driving the vehicle to increase pressure is not advisable because it may exacerbate the problem if the compressor is malfunctioning. Releasing air to reset the system does not address the root cause of the low pressure, and could potentially lead to further complications. Replacing the air gauge might be considered if it is confirmed to be faulty, but without proper investigation of the compressor first, it does not solve the issue of why pressure isn't building up.