Just bought a new 389 and wondering what these 2 switches are for. Nobody at the dealership knew. My build sheet said spare EOA switch. When I activate them, the switch lights up, but I’m not hearing any air actuation.
With the way things are spoken, written, and read, nowadays. The makers probably thought the switch production order said to print “air” instead of “spare”.
Then of coarse no one in quality control cares to correct it when they see it anymore.
They are Spare electric air switches for example if u wanted to add a Air over ride on air bags u would just buy a Electric air shut off / open and wire it to that switch. Some trucks are even called Aux