04 silverado electrical

[bootlife]

Ok I got a new harness for the headlights to day and the new harness has a red Hotwire for the fuse box. Any idea wat it powers? Old harness didn't have that. Also came with a small fuse box that mounts beside the big fuse / relay box. Any idea wat that's for? If u have a fuse diagram for the little 1 that would help. Last thing. I also picked up this little sensor thing that goes around the neg batt cable, my 20oo don't have this. It plugs in to a purple plug out of the electrical area. Wats it for?

[blacstar]

u bought a '04 harness for a '00 truck. start there!

[bootlife]

No, iv had a 2000 z71, I just got an 04 2 wheel drive with a 6.0 swap, I'm trin to get the electrical right on it.

[bootlife]

Ok I fig it out, the extra fues box is for factory elec fans, any ideas what the thing around the batt cable is for?

[rkwhite61]

Are you talking about a lose connector inside the fuse block? I think that may be used for 4wd. I recall having that plug which wasn't needed on my 2wd. I also had an thick red wire that wasn't used and I think that was for a trailer brake set up. But, mine is an '02 harness.

[bootlife]

No it's off a 2wd, it's was a fuse block for the factory fans I fig it out. I'm tring to see what the thing is that goes around the neg batt cable and plugs in to the harness

[MrHorsepowerLSx]

Heavy (blue) 10awg wire is for electric brakes.... if you have factory 7 way there would be wire from rear of truck plug all way up to front of engine bay.

Heavy (red) 10awg wire with a small eyelet is for 12vdc Battery charge, that wire also runs to the back of the 7 way plug.

Now depending on how well equipped your truck is with factory opinions it might just be a "plug and play" and you will not need those wires.