While driving a vehicle with a dual air brake system, the low air pressure warning light and buzzer activate, meaning pressure in one of the two systems has dropped below 55 psi. What should you do?

AAMVA CDL Manual, Section 5.2 (Dual Air Brake), p. 5-5; 49 CFR 383.111(b)(6)(iii) (pressure levels at which low air pressure warning devices should activate)

This is a critical go/no-go decision point for a professional driver: ignoring a low-air warning in a dual system can mean driving with only partial braking at one end of the vehicle, significantly extending stopping distance and increasing crash risk.