Kevin8520

On an 03 Silverado 2500HD w/ tow package is there a prewire harness under tha dash? I can not seem to locate it if there is one, all I can see is the OBD connector. I will be wiring a Prodigy controller.


Thanks!

Kevin

Old Coot

I had a Prodigy Contoller on my 2003 and as I remember the harness was between the console and the firewall.

ZX1100F1

The brake controller wire pigtail was a seperate item provided in the glove boax on the 03 models, if you no longer have the pig tail you can get it from any GM parts center.

Old Coot

You may be right on that. It's been about 5 years since I put it on the 03. I got to looking and found this letter from Chevrolet. June of 2003
Dear Chevrolet Customer,
As the owner of a Chevrolet 2003 model year full size truck, your satisfaction with our product is of utmost concern to us.
If you have a trailer equipped with electric brakes, and use a trailer brake wiring harness from a prior model year, we wouldlike to make you awarethat following conditions will occur:
1. When your vehicle headlamps or park lamps are turned OFF: Your electric trailer brakes may not apply when the vehicle brakes are applied.
2. When your vehicle headlights or park lamps are turned ON: Your electric trailer brakes will apply without your vehicle brakes being applied.

Trailer brake wiring harnesses from prior model years are not compatible with your 2003 model year because the electrical systems are different.

To purchase a new harness for your 2003 model year vehicle, contact your local Chevrolet dealer and order GM part number 15085418.
Your satisfaction with your Chevrolet vehicle is very important to us and we are sending you this information to ensure that your ownership experience is a pleasurable one. Please keep this letter with your vehicle owner's manual for future reference.

Kevin8520

So with the pigtail from chevy will it simply plug into the wiring block under the dash and the other end directly into the prodigy? or is there still splicing needed? I thought I was set and then I found this link: http://www.rv.net/forums/index.cfm/f...d/20224935.cfm and now im confused all over again.


Thanks
Kevin

Kevin8520

also, it seems that I have found the 6pin wiring block under the dash... its under a plastic cover near where your left foot would sit while driving... it is a 6 pin block with what looks like 4 active wires in it. However, on my actual 7way trailer connector next to the hitch it looks as though the blue trailer brake wire is not attached.. its just hanging there with a littleblack cap on it. Anyone know anything about this?

BTW I wired up my old Dodge with no problem... guess I just gotta learn the chevy wiring schematics.

Thanks again everyone!

Kevin

CrockJock

They (GM) moved one wire on the brake wiring harness to make everything difficult! They make it sound like there is an elaborate wiring change, but it's not. Move wire from brake controller harness slot A To D either by cutting and splicing or changing in the plug. You can put D to A but this wire wasn't even connected to anything on my 2001 GMC connection. It's very simple. This worked moving my wiring from my 2001 GMC Sierra 2500 HD to my 2003 Chevrolet Silverado 2500 HD.