Enabling Gmc Yukon Factory Tow Hitch

mclalaska · January 5, 2009

I have a factory installed tow hitch and electrical harness on my 2007 GMC Yukon Denali XL. I went to use it for the first time recently, and found that the electrical part is dead. The book says I should call the dealer. Of course, I want to solve it on my own.

Question: Is there an additional connection, fuse, relay, switch which I need to install/click etc - even on a factory installed tow package - to start using it?

Thanks in advance,

Z45 · January 5, 2009

Mine worked from day one. Are you just concerned with lights etc or trailer brakes? Trailer brakes won't work without a controller.

mclalaska · January 5, 2009

Just lights... in fact I am trying to use it for a set of auxiliary back up lights... But I tested the center post of the connector and it is dead. I also tried the lights separately on another vehicle and they worked perfectly.

sigh...

mclalaska · January 5, 2009

Also...sorry for the multiple postings..I kept getting an error but I guess it posted anyway.

AirForceAngler · January 6, 2009

Not sure about the back-up lights, but to have the 12V power and brake controller, there are 2 wires that need connected to the two posts at the under hood fuse block. The wires are taped up to the harnesses on either side of the block. You will also need at least one fuse to put in the block. Not sure where it goes on your truck. Mine was a square, 30A fuse.

opus8844 · January 6, 2009

I just went thru this with my new Suburban here is what got me through it This from Tekonsha it helped me hook up my Prodigy real good instructions

good luck it is the two wires on the studs you need to hook up under the Hood

prodigy.pdf

snarkee · January 6, 2009

do you mean when you plug in the trailer harNess you do not get auxilary power? if this is the case then there is a red wire taped up near the firewall by the fuse panel.....it has an eye on the end that i attached it to the spare post in the fuse box....i added a green square relay/fuse (i forget what amp).....now i can run my fridge in my travel trailer by using the truck power.

just follow the diagram above!

if you meant something else then forgot what i just said lol

mclalaska · January 6, 2009

TahoeMike and Opus:

You guys were right on.. I am just back up from the garage and your advice did the trick! Many many thanks. Happy New Year! I needed those lights up here in dark Alaska!

Sean