Fog light isn’t working

[omarrrr239]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving great advice from the knowledgeable folks on this Forum. Check the ground wires going from the fog light bulb socket to ground, somewhere close by on the frame. These trucks are very sensitive to corroded grounds. If you have a multimeter, check for continuity between the ground contact in the fog light bulb socket and the truck's frame.

 

[Doubeleive]

does the light on the switch inside the vehicle light up when you press the button?

 

[omarrrr239]

does the light on the switch inside the vehicle light up when you press the button?

Like to button to turn them on? Yes it’s on whenever I turn the lights on. I’m not sure if I’m answering your question, let me know

 

[02Z71Raven]

Like to button to turn them on? Yes it’s on whenever I turn the lights on. I’m not sure if I’m answering your question, let me know

Specifically need to know if the LED that backlights the button that you press turns on.
There is a 10amp fuse in the panel in the side of your dash. I think it's for interior illumination. If you haven't checked ALL those fuses yet, I would stop and do that first.

 

[Doubeleive]

Like to button to turn them on? Yes it’s on whenever I turn the lights on. I’m not sure if I’m answering your question, let me know

the fog light button should not be lit unless you have the pressed the button first (key-on, low beam, or no headlights switched on), if the fog light button is lit always with key on then you have a short somewhere.

 

[Fless]

These should be listed in your owner's manual.

Underhood fuse and relay, verify fuse is good and has power on both sides, and swap the relay with a known good one (horn?).



In-cab relay / fuse center, verify power through #14 for backlighting as @02Z71Raven mentioned.

 

[omarrrr239]

Specifically need to know if the LED that backlights the button that you press turns on.
There is a 10amp fuse in the panel in the side of your dash. I think it's for interior illumination. If you haven't checked ALL those fuses yet, I would stop and do that first.

 

[omarrrr239]

This is what it looks like when the low beam is on.

 

[omarrrr239]

I check all the fuse and relay for the fog lights and still nothing I’m getting power from the switch but nothing to the relay under the hood. There’s something going on from behind the switch to the relay

 

[Doubeleive]

can't tell if that is lit up or not, when the plastic wears off it will show up as that blonde/natural color plastic underneath.
you stated that you replaced the switch already, does not appear to be the case based on your photo.
per your initial post.....
"I need help in why my fog light isn’t turning on in my 02 Yukon. I replaced the fuse, the relay and the switch"