Peterbilt 579 wire question

I have a 579 and a Minimizer seat that needs power
In my last truck I just added a new fuse and ran a wire back to the seat

I have this connection that’s already behind the seat and assume it should be hot or able to be but either I am not getting a good ground with my test light or there’s a fuse for it that needs to be installed
Any ideas?

 

With all the computers in there now it may have to be turned on with a laptop.
@pushbroom @Goodysnap

 

I show a fuse for driver heated seat. N12

 

not to highjack the thread but @Long FLD any chance you could PM me a picture of your fuse cover if its a 17 579? More then 3/4th of the diagram in mine is missing....someone aprayed something all over it before i bought it and having an intact one would be useful.

 

Yes. I’ll get a pic of the whole thing later.

 

Much apprecated!

 

Which fuse box is this?
The one by my drivers footwell is not like this

 

That’s the one by my left foot.

 

Yeah
Not seeing it there or on the firewall one
I do have a 2021 so maybe it’s changed

I do have one under the bunk I will also check
Maybe there?

 

If there’s no fuse then it might be something controlled by the cab control module like @062 said. I’m out of guesses if you can’t find a fuse for it.

 

Might be a seatbelt buzzer wire. Lol