I have a 2001 Dodge Ram 2500 diesel and my fog lights don't work. I hear that the headlight switch could be the problem. How do I test it? Is there something that shows what color wire on the harness that goes to the headlight switch is for the fog light?

 

You can grab the 01 service manual from here. Wiring diagrams are in section 8W. Look at front lighting. Will tell you more than you really wanted to know.

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