Trailer Wire Harness

zorrro · August 2, 2005

Hey,

I'm getting ready to haul a camper in my '01 2500 HD. I'm running the camper through my 7 pin connector in the rear. Lights seem to work fine but, I have no 12v feed for accessories inside the camper (No power at the plug). According the GMC owners manual, I need to install that trailer-brake wiring harness and fuse that has been residing my glovebox. Is this right? If so, the manual just says have a dealer do it! Has anyone done this? It doesn't look like a dealer job to me. Thanks for the help............Zorrro

Shaners · August 2, 2005

The "Maxi" fuse goes in the electrical center under the hood on the drivers side wheel well. I believe it goes in the "Stud #2" location...

sonjaab · August 3, 2005

Heres a link with pics and where to put the fuse in

http://www.fullsizechevy.com/forums/showthread.php?t=164069

zorrro · August 4, 2005

Thanks guys!

I needed to put the 40a maxi-fuse in STD #1. I now have auxillary power for my camper etc. I did not have to hook-up the trailer-brake wire harness as the owners manual makes it sound................Z

lawnmaster5000 · August 14, 2006

Thanks guys!

I needed to put the 40a maxi-fuse in STD #1. I now have auxillary power for my camper etc. I did not have to hook-up the trailer-brake wire harness as the owners manual makes it sound................Z

<{POST_SNAPBACK}>

I am having the same problem with the Aux power to the trailer.

I have an '06 with a duramax and the dual battery set up. according to the owners manual it says to NOT install a fuse into STD # 1 with the dual battery. My truck came with the STD #2 containing a 30 amp fuse. According to everything I have been able to find here and at the dealer my aux should have power but when tested at the harness there is nothing.

Am I still missing something? Can someone please let me know.

Howard · August 15, 2006

I am having the same problem with the Aux power to the trailer.

I have an '06 with a duramax and the dual battery set up. according to the owners manual it says to NOT install a fuse into STD # 1 with the dual battery. My truck came with the STD #2 containing a 30 amp fuse. According to everything I have been able to find here and at the dealer my aux should have power but when tested at the harness there is nothing.

Am I still missing something? Can someone please let me know.

<{POST_SNAPBACK}>

Scott, I have an 06 D/M also. Did you plug your brake controller into the the receptacle second from the left? Im waiting for info on the fuse too.

HMS

Shaners · August 15, 2006

Check for a fuse sitting in an unused recepticle. I think that is where I found mine for my Dmax. I just pulled the paper of of it and relocated it... the controller works fine!

That was awhile ago, so I may be slightly off with my idea, and the '06 may be different...

lawnmaster5000 · August 15, 2006

Yes the brake controller harness connects in the second slot from the left. The fuse that came in your harness is not needed to make the brake controller work if you have the HD and towing package.

My problems are not with the brake controls (although i did have problems with that too since they switched the two wires since my '00.) I am trying to figure out how to get aux power to trailer.

if anyone knows thanks for your help.

shaners,

do you remember where you found the fuse and the unused recepticle?

There is only one J style fuse slot open in the under hood box and it is the STD # 1 which according to GM needs to remain empty. - thanks

Mattt · August 15, 2006

On my 2001, Both #1 & #2 need a fuse in them for the trailer wiring to work. I dont remember which is which, but they both need a good fuse in them. I dont know about the 2006. I looked at the pics posted on FSChevy.com by lawnmaster and that fuse box is different from 2001.

The small harness in your glove box is only required to hook up an electric trailer brake controller, it has nothing to do with feeding power to the trailer 12V system.

Zorro, Does your trailer not have brakes? If it does, you would need the pigtail pluged in above the drivers feet to make the trailer brakes work thru your brake controller.

Shaners · August 15, 2006

shaners,
do you remember where you found the fuse and the unused recepticle?

There is only one J style fuse slot open in the under hood box and it is the STD # 1 which according to GM needs to remain empty. - thanks

<{POST_SNAPBACK}>

I remembered when I went to bed last night... The fuse was with the supplied pigtail in the glovebox.

There was a dummy fuse under the paper in the under the hood electrical center. I removed it and installed the supplied maxi fuse in it's place.

I didn't use the supplied GM pigatil, because i bought a pigtail that was already prewired for my Tekonsha controller (no splicing).

lawnmaster5000 · August 16, 2006

oops - double post

lawnmaster5000 · August 16, 2006

well neither i nor my dealer have been able to figure it out yet. If you are having the same problems or have ideas on an answer check this topic. I have posted in a nearly identical thread there.

Full Size Chevy Forum

Thanks for your assistance.

- Scott M

lawnmaster5000 · August 24, 2006

My dealership put a fuse into std 1 and now everything works as it should. I dont understand why GM would say to not put a fuse there when it is required.