trailer lights have no power?

1998 GMC JIMMY
130,000 MILES • 4.3L • V6 • 4WD • AUTOMATIC
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JAMES CUNNINGHAM
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The fuse has a block of 6 fuses all related to the trailer wiring and there is no power to any of them. I was starting to install a trailer plug and i did have power and then lost all power at the plug and the fuse box. Is there a relay for this?
Jul 28, 2023 at 2:26 PM
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JACOBANDNICKOLAS
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Hi,

I attached the wiring schematic related to the exterior lighting. The trailer circuits are included in the schematic. Which fuses did you lose power top? I highlighted everything I could find relevant, but I need you to confirm which fuses don't have power. Once I know that, I can go to the power distribution schematics and see where the power is coming from.

I did notice that the schematic indicates all of the fuses are in the under-hood fuse box. Is that where you are having the issue?

Let me know.

Take care,

Joe

See pics below.
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Jul 28, 2023 at 9:40 PM
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JAMES CUNNINGHAM
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The fuse block in my jimmy has a group 0f 6 fuses all labeled like trl l turn or trl r turn and none have power. That was yesterday. Today everything works except the L rear trailer light. These are new sealed type lights and I am thinking it may be a defect, I ordered another set and will see if this the problem. I am 89 years old and in this business most of my life and not seen this before. Thanks for your response, I will let you know.
Jul 29, 2023 at 5:56 PM
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JACOBANDNICKOLAS
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Hi,

Are you getting power to the light? If you have power and ground, the light should work. If it doesn't, then as you said, you likely got a faulty light.

If you have a chance, let me know how things turn out for you. I'm interested in knowing. Also, any idea why there is power today but not yesterday? That's an odd one.

Let me know.

Joe
Jul 29, 2023 at 8:59 PM
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JAMES CUNNINGHAM
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The new light solved my probem. The other thing acted like a circut breaker, bur I did not see any thing like that or a relay. Very strange that that entire corner of the fuse block was dead. I can't understand how it came back. Thank you for your help.
Aug 2, 2023 at 11:06 AM
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JACOBANDNICKOLAS
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Hi,

Thanks for the update. I'm glad to know you got it taken care of.

Take care of yourself and feel free to come back anytime in the future.

Joe
Aug 2, 2023 at 7:38 PM
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JAMES CUNNINGHAM
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Thank you for your help and if I have any other issues I will be in touch, I have owned 3 auto shops in New Jersey and a 14 bay body shop and auto repair in San Diego CA and never saw anything like this problem. I am too old to do this kind of work professionally but I still do a little on my own stuff.
Aug 3, 2023 at 9:22 AM
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JACOBANDNICKOLAS
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Hi,

Wow, you've done a lot. Interestingly, I feel the same with my age, but find it challenging to find resolutions to some of these crazy issues. LOL

Regardless, take care, and as mentioned, feel free to come back anytime.

Joe
Aug 3, 2023 at 8:31 PM