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Trailer harness has no back light

C

Copperdesigno

Full Member
Joined
Dec 30, 2007
Messages
21
I have been searching but can't seem to find a solution.  I installed a backup camera and found out I have no power to reverse light Pinon the harness.

I installed the fuse under the hood in post 1 for 12v.  I tested  the 10amp trailer backup fuse and it is good. I am missing something but not sure what. Thanks
 
This may sound like a dumb question, but how did you test it. It maybe be on a ign/run circuit.
 
I tested it with volt meter and the truck running and in reverse.  Person was in cab making sure I didn't get ran over :)

I also checked the 3 BCM fuses in the fuse block inside the cab.  But that should affect the trailer harness but just checked to be safe.

 
Check harness behind trailer plug and the junction point that corrodes under rear of truck
 
Thanks

I unplugged the harness behind the plug and that had no power.

Is there another place in the harness that I could check?
 
Do you have left turn, right turn, running, and brake lights at the trailer harness connector?
 
Copperdesigno said:
Thanks

I unplugged the harness behind the plug and that had no power.

Is there another place in the harness that I could check?
Click to expand...
Follow it back. there is another junction block connector in one of the corners.
 
I do have power for all of the other pins (turn signals, brake,etc)  just not reverse lights?

I did see that junction on the drivers side. It only seemed to be for the tailght.  I'll trace the wire loom further and try to find another junction.

Thanks for the input guy .
 
Tapping into the lights is plan B. I bought the hopkins b/u camera due to the plug that snaps between the harness and bumper plug. I didn't want to splice into my wires but if I have to I will.
 
I would go double check the fuse with ohmmeter and maybe the wire underneath.

Seems too simple if the other wires work and just the reverse not
 
Thanks. When I get more than a few minutes I will go though each fuse again before digging into the wiring. 
 
I double checked all the fuses with an ohm meter and they are good. I checked that the "TRL b/u"fuse socket and I have power there.

I jumped power from the running light pin to the backup light pin with the running lights on.  The camera system operated as expected.  So the system works.

Next I plan on b dropping the spare tire and try to trace the wire. 

So much for being an easy install.

 
Copperdesigno said:
I double checked all the fuses with an ohm meter and they are good. I checked that the "TRL b/u"fuse socket and I have power there.

I jumped power from the running light pin to the backup light pin with the running lights on.  The camera system operated as expected.  So the system works.

Next I plan on b dropping the spare tire and try to trace the wire. 

So much for being an easy install.
Click to expand...


Before dropping your spare, check under the passenger side rear quarter panel all the way at the back of the truck.  That's where I found my junction panel located on my 2500.  This flat piece of plastic has four connectors on it that feeds license, left, right, tail, brake, and reverse lamp circuits for both left and right taillamp assemblies.

On some pickups this same junction box is located on the frame cross member ahead of the spare.  Not sure what vehicle you have, and whether it is a 1500 or 2500.
 
Just wanted to check which wire on the vehicle side trailer plug were you looking for Reverse to light up on?

Center pin, right?

 
Center pin is my backup lights per the wiring diagram and color code of the wire.

I have the 1500 avalanche, I'll look for for a junction. 

Thanks
 
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