Low air buzzer and light will not go off on FLD120 Freightliner?

If the low air buzzer and light on a FLD120 Freightliner won't turn off, it typically indicates that the air pressure in the system is below the required threshold. Check the air pressure gauge; if it's low, inspect the air system for leaks, ensure the compressor is functioning properly, and verify that the air governor is working. Additionally, check the condition of the air tanks and lines for any blockages or damage. If the issue persists, consulting a professional mechanic may be necessary.