Fog Lights Inop, It Is Not The Switch

[knightgang]

My Fog lights do not want to work. Just got int he truck one day and pushed the button to turn them on and nothing. the little orange indicator light in the switch will not light up and the bulbs will not come on. I have checked the fuse, it is good. I have swapped the relay with a known good one, nothing. The strange thing is that the cargo light (which has its button on the same switch block) works just fine. I have also replaced the switch block with a new one and still, cargo light works, but no fog lights...

 

Where else should I start looking? Does someone have the wiring diagrams for these circuits to help me troubleshoot this issue...

 

Also, is it true that all of the lighting controls run through the Body Control Module? If that is true, is it possible that the BCM has a bad circuit in it? Cant his be tested? If it has to be replaced, does it have to be programmed?

[Daryl LBZ]

Try taking the switch out and check the wire. If you use the Fog Lights alot sometimes the orange indicator light being on gets hot and melts the wire behind it causing the lights not to work. My dad had this problem with his 99 Silverado, only it happened with the 4wd Buttons instead. Sometimes his fog lights don't want to come on either so the same thing is probably happening to his.

[Ezrider_92356]

headlights have to be on for the fog lights to work and its posible both the bulbs are burned out as well

[knightgang]

headlights have to be on for the fog lights to work and its posible both the bulbs are burned out as well

 

I know that...... I can properly operate my truck. I was looking for reason that they would not work under the proper operating conditions...

 

I determined that there is indeed a problem with the Body Control Module. I decided to by-pass the need for the body control module for this particular function. Everything is not working fine...