Under hood fuse box upfitter connections

[Handler]

Gents,
I'm looking into installing an electric fan system on my 2003 AWD Astro and hoping for some clarification on the Upfitter connections of the underhood fuse box. Reading https://sites.google.com/site/astrosafa ... /aux-power it says the "A" stud of the Upfitter connections to be switched but I find this stud to be hot at all times. Can anyone clarify how these Upfitter connections work ?

Many thanks for your time.
-rick

[The Drummer]

On mine ( 2000 ) its as described in the link , stud a is switched and b hot at all times , i dont know , maybe your year is diffrent , maybe its been modified , maybe try switching the relay with an adjascent one to make sure its good ,i realy dont know anything else about it , but someone that does know will be here shortly i am sure .

[1lowcab]

Mine are both hot all the time.

[markmitch]

I have an e fan and have no idea where you got the term upfitter from can you explain what it means?

[1lowcab]

I don't know if the gen 1 vans have it or not. On ours there is an underhood fuse box with 2 large exposed studs that are marked "upfitter". One is supposed to switched power the other is supposed to be constant hot, both have 30 amp maxi fuses.

[Old Barney]

They are both hot all the time. The ignition relay has 12 all the time on one post (contact) When you turn the key on it energizes the relay and directs 12volts to the ignition circuit. There should be two up fitter fuses one for A and one for B. They are HOT all the time.

[WinnieVan]

Usually I'd pipe in something about how you didn't search the forum enough -- but this one would be wayy to buried to find:

I just looked into this - it looks like both upfitter studs are always on but the upfitter ignition stud is hooked up to a relay that flips under IGN.

Now getting to the other side of that relay is a mystery to me... I suppose you could trace the wire from the relay to figure out how to tap it -- but I doubt it goes to a stud anywhere.

Would be cool if one of those studs was IGN power and one was ALWAYS HOT. Oh well!

Found it Winnie! Under dash Convenience center left of Fuse panel. Haven't confirmed yet but being a Upfitter relay is under hood I am guessing A or B is key on other one is constant

1996-1999




Not sure what Upfitter battery is for on the left there

CFM has since verified that one of these is a Key On power source that you can tap with a female blade connector!

[Old Barney]

The other up fitter is for things like trailer brake controller and some conversion van accessories.

[WinnieVan]

Are you talking C6? Or one of the A/B ones?

[Handler]

Just to be clear, I have a 2003 AWD and a 2004 RWD which both have power on the upfitter studs "A" and "B" at all times as others have reported.
I'm adding a diagram that shows the underhood box and I'm trying to understand the function of the Upfitter Ignition relay and does it have anything to do with the Upfitter ignition power stud ?

[WinnieVan]

Handler see the post I made a few up...

The other side of that relay is in the interior fuse box... @C200. I don't remember if it is A or B that is accessory power... but one of those connections is the downstream side of that relay. The upfitter ignition power stud is on the upstream side of that relay -- so that's why it is always hot.

[CopperFiremist]

[Handler]

Many thanks WinnieVan ...
"The other side of that relay is in the interior fuse box..."
Now, that makes sense to this old brain.
Thank's to all.

[markmitch]

OK sorry for jacking your thread. The closest thing to that on a first gen van is under the hood under the front side of the fuse block there is one hot all the time stud. Thanks for filling me in guys. markmitch