Low Air Pressure Light Won't Go Off

[Viva Las Vegas JDR]

Low Air Pressure light will not go off. Start the engine builds air to 140 by gauge but light stays on. Several applications of service brake to bring pressure below 80 by gauge air rebuilds as it should but light stays on. Maintenance book tells how to test sensor but I'm not sure how to test it.

JDR

[NewellCrazy]

Go to any napa store in our area that has semi stuff and tell them you need a new low air pressure sensor.

Sean

[GORDON HUMMEL]

It's called an LP-3.
If you go to the manual section of the forum, page 67 of the Bendix manual has the info.
They come in various cut out pressures.