A low air pressure warning signal should activate: Do you currently have car insurance? Insurance is mandatory to drive in Ohio Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question A low air pressure warning signal should activate: Answers When tank pressure falls below 120 psi. When tank pressure falls below 55 psi. When tank pressure falls below 10 psi. Explanation In an air brake system, a low air pressure warning signal must come on if air pressure in the tanks falls below 55 psi. This warning signal may come in the form of a light, a buzzer, or a wig wag.
