Hey, long time reader first time poster.
just picked up my second 2nd Gen, 2001 2500 diesel. and having a headlight issue. I’m in Canada and so have daytime running lights, they’re working. High beams also work when I pull the blinker switch and hold it, but regular light function isn’t working. Single bulbs not quad. Doesn’t seem to be a relay for this model in the relay box. Pulled the headlight switch and cleaned the contacts there, might pull the multifunction switch next to look for something obvious there, any tips on diagnosis?

 

The headlight flash feature bypasses the headlight switch so I would start there (again). Pin 6 (light green) should have power at all times. Pin 5 (black/orange) is the pin that the switch connects to when the headlights are turned on. You could jump 5 and 6 and if the lights come on you know the problem is internal to the switch.

 

Thank you for that advice, found the problem on the multi function switch, one dirty pin. Cleaned it up and things are working!

 

Good ! Do you remember if it was the light green wire ?