Vacuum blows out fuse

side panel ? near door ?

 

Awhile back the electronic industry came out with a product that is a "resettable fuse." There are two current levels that these things react to... a overload rating and a maximum rating. At the maximum level, it opens permanently like a common fuse. At the overload level it opens - but after the device cools (all fuses react to the heat caused by the current flow through it) it resets itself, and will carry current again.

Maybe there's a couple of loads on that circuit - if all are on at the same time it will overload the fuse, but alone, the vacuum will not exceed the overload rating of the fuse.

 

Did you just look at the fuses or pull them and test each one with a meter? You could have a "short stop" style of breaker that will automatically reset itself.

Most of the trucks I've driven with the battery saver unit on them kill the entire cab and sleeper to save the main batteries. I had one of those go bad and we could only run the bunk heater for about 5 minutes before it thought the batteries were low.

 

Sounds like you have a low voltage protection unit. When the voltage drops to a certain point it will disconnect certain items. like accessory outlets and interior lights. Usually there might be a beeping sound when it activates.
Try running the vacuum while you have your engine running (except in California!)

 

Thats what it sound like to me low voltage protector

 

well there ya go--nothing wrong with the truck and that is good--and you learn something new everyday
now hopefully it isnt like in the columbia's and screws up--then things can get messy