Electrical/Air Issues

While driving my '04 780, the message center on the dash board looked like it was having a seizure, toggling between my airbag dump valve being activated to my fifth wheel slide being unlocked to my power divider being engaged. I pulled off to the side of the road and everything seemed fine, but there was a faint smell of something electrical burning or burnt. After climbing under the truck, I could not find anything. I drove the truck down the road and it seemed ok. I did notice that all the electronically controlled air systems were inoperable. Air horn, Power Divider, Air Bag Dump Valve and Fifth Wheel Slide. I am assuming that there is some master control module or solenoid control valve someplace under the truck. Would anyone have any ideas of where this part is located? What it is called? and how hard it is to replace it? Any help is greatly appreciated.

 

Thank you, I will check it out when I get done at the end of the day.