Anyone know what this light is?

[Woodnut36]

I’m starting a new bus life and I have a light I don’t recognize . 2000 bluebird all American. It’s comes on when the brake is pressed with the engine running or off. Air brakes work properly with no leaks. It is on the left side of the dash and is a circle with a line on the left of it.

[JackE]

It's tied into the electrical circuit of the brake line. It lets you know when the brake lights are receiving power.

[Woodnut36]

Thank you. I was spooked because a guy I had doing something else said it was a short. Everything I was reading said it was normal to see it as long as it goes off. I appreciate you responding