Trailer Wiring Problem

AllZWay · July 7, 2011

I have an '07 Tahoe that I am having a trailer wiring problem.

All lights have power with the headlights on, but the left blinker and left brake light do not work only the taillights.

I have proven that the problem is not with the trailer lights by connecting to the trailer to my truck where all lights worked correctly.

This make the problem with the wiring on the Tahoe and it appears to just be with the trailer wiring connector or wiring to the connector.

Anyone had this problem or want to give me some ideas of where to start my real search for the problem?

Thanks,

James

wavery · July 7, 2011

I have an '07 Tahoe that I am having a trailer wiring problem.

All lights have power with the headlights on, but the left blinker and left brake light do not work only the taillights.

I have proven that the problem is not with the trailer lights by connecting to the trailer to my truck where all lights worked correctly.

This make the problem with the wiring on the Tahoe and it appears to just be with the trailer wiring connector or wiring to the connector.

Anyone had this problem or want to give me some ideas of where to start my real search for the problem?

Thanks,

James

Scroll down to the 7-Pin diagram:

http://www.etrailer.com/faq-wiring.aspx

See pin #5? Take your test light and clip it to a good ground on the truck and touch the probe to pin #5 with the left T/S on. If the test light flashes, the problem is not the truck.

Let us know how that goes and one of us will walk you through tracing the issue.

AllZWay · July 8, 2011

I am going to double check this afternoon, but I am pretty sure there is no power at that pin at the back of the Tahoe. I hastily checked it with a volt meter, but can't specifically remember if I checked every pin.

I'll post back.

Thanks,

James

wavery · July 8, 2011

I am going to double check this afternoon, but I am pretty sure there is no power at that pin at the back of the Tahoe. I hastily checked it with a volt meter, but can't specifically remember if I checked every pin.

I'll post back.

Thanks,

James

Just a tip on trailer harness wiring......... I always solder the end of each stripped wire before I put them in the connector. It makes it a heck of a lot easier to get the wires in. It also keep the small strands together so they don't stray to another connector and make all sorts of weird issues....

GPSilverado · July 9, 2011

I am not sure about your model Tahoe, but a lot of the newer trucks have a separate fuse for the trailer turn and brake lights. Not sure if there is a separate one for left and right though.

I do remember several posts where people had problems with the left turn and brake, and it turned out to be a problem with a controller, and required a reprogram or replacement from the dealer.

AllZWay · July 9, 2011

I don't have any power to pin 5, but do have 12v at pin 6.

Is it possibly at the back of the connector where is passes through the bumper? It was too hot out tonight to spend much time with it, but is it easy to remove?

The tahoe lights themselves work, it just at the connector that it doesn't.

wavery · July 9, 2011

I don't have any power to pin 5, but do have 12v at pin 6.

Is it possibly at the back of the connector where is passes through the bumper? It was too hot out tonight to spend much time with it, but is it easy to remove?

The tahoe lights themselves work, it just at the connector that it doesn't.

My factory receptacle just turns about 1/4 turn and pulls right out. I'm not sure about the Tahoe. Are there any visible mounting screws?

I think that you may find that the #5 connector screw is loose and the wire isn't making contact.

Blue2500CC · July 10, 2011

I don't have any power to pin 5, but do have 12v at pin 6.

Is it possibly at the back of the connector where is passes through the bumper? It was too hot out tonight to spend much time with it, but is it easy to remove?

The tahoe lights themselves work, it just at the connector that it doesn't.

As mentioned, your truck should have seperate fuses under the hood for the trailer lights. Double check those before tearing the plug apart.

Good luck!

Chris

AllZWay · July 11, 2011

I don't have any power to pin 5, but do have 12v at pin 6.

Is it possibly at the back of the connector where is passes through the bumper? It was too hot out tonight to spend much time with it, but is it easy to remove?

The tahoe lights themselves work, it just at the connector that it doesn't.

As mentioned, your truck should have seperate fuses under the hood for the trailer lights. Double check those before tearing the plug apart.

Good luck!

Chris

I am really embarrased to say this, but I didn't realize there was another fuse panel and I did have a couple blown fuses under the hood. I am not sure what blew them, but it back working now.

Thanks for everyones help.

James

Blue2500CC · July 13, 2011

James,

No need to feel bad or embarrassed! How else do we learn if we don't ask!

Main reason I knew about the seperate fuses is a family member was having trailer light trauma like you, and I started checking fuses, not knowing the truck lights still worked. Noticed some labeled "trailer".

It is a nice feature to have. I have had trailer light trauma myself on a trip, unprepared without any tools, and had the "old style" fuse set up that blew the truck lights also. What a pain that was!

Glad you are all set!

Chris

ps: It probably was that darn fuse gremlin!

dixonlaredo · August 4, 2011

I just installed my electric brake on my 2007 Sierra. all the lights and turn signals work; just not the electric brakes. Does this sound like a blown fuse as well?

**Ok, I see I still have two wires under the hood fuseblock to hook up, duh**