Trailer wiring harness 07 GMC Sierra

[cnodie1]

Whats the best way to pop off the 7 blade plug on the back of my truck? I'm not getting power to one of my lights on all of the trailers I hook up to. I have also tried different adapters including ones that have little LEDs on them and they also show I'm not getting power to one of the blades. I tried getting the plug off to check it with a tester but I can't get the dang thing off.

Could it be a fuse out? Help me out Vince!

 

[Blackhawk]

Follow the wires out of the back of the plug to the "Y" where it interfaces with the truck wiring harness. Most harnesses nowdays are this type. Unplug and inspect the blades and sockets, clean as necessary, coat with silicone grease and reassemble. Hopefully this will fix it.

If your plug is hard-wired into the harness by an aftermarket shop, sometimes crimp connectors are used which pierce the insulation and connect to the wire via a slicing action. These often fail and should be replaced with good terminals or, even better with cut/strip/solder/heat shrink tubing.

I've often found that the ground is a problem on some connectors, both the trailer end and the truck end. Try reseating the ground and see if it helps.

 

[cnodie1]

I will give that a try.

 

[3fifty7]

First thing I would check is each blade with a test light or multimeter grounded to the frame.
Then confirm all fuses are good.
Then check wiring harnesses

 

[The_Shadow]

There are seperate fuses for the trailer wiring as opposed to the truck lights.

 

[LNSvince]

Man Im sorry, I am just now checking this.
Be more specific on which light your speaking of and Ill look up the wiring diagram for the best case scenario.

But yes, check the grounds and the factory connectors under the truck near the bumper. make sure no wires have been pulled, chewed, etc.
Is it the factory trailer tow wiring harness ? or was it added.

Vince

 

[LNSvince]

Do all of your rear truck lights work ? Do they actup when the trailer harness is connected ?
Check your owners manual for the inside and underhood fuse boxes .'

This is a good time to mention :

EVERYONE, seriously, Read your owners manuals. You will be surprised and may learn a thing or 2

 

[cnodie1]

It was a blown fuse. I hook up to a lot of old shitty trailers and probably found one with a short. That's for all the help fellas. Look for another thread in a while asking about power mirrors popping fuses lol.

 

[LNSvince]

I was not receiving emails when someone opened up a new thread. Spanky fixed me up.