BlueBird control panel switch question

[Nick969]

My bus has a switch labled "BRK/OVD" does anyone know what it does its a momentary contact panel switch to the left side of the driver seat along with lights etc.

Thanks in advance

 

[o1marc]

Brake override switch—Optional.The brake interlock system is a safety feature. The system does not allow the vehicle to be moved with the doors ajar. This switch over-rides the system enabling the vehicle to be moved while the doors are in the open position.
NOTE: For emergency purposes only.