Hey all thanks in advance for any help! I have no low beam. High beams work, running lights work, fog lamps work. Fuses are good, when checking have no power on coming to head light plug in on low but do on high beam. Even after no power I replaced bulbs. After checking several sources was told to replace Dimmer/multifunction switch. Did that today still nothing. I have a Boss plow as well. To take that out of the equation(I think) I went direct to factory wiring plug after unhooking from plow wiring. Any thoughts?

 

Oh one more thing I forgot! Earlier this year head lights would just cut out. If I flipped headlight switch from just running lights back to lowbeams they would come back on.

 

Man things are changing. I just got access to some 2010 diagrams. No more regular 12v circuits to make the lights work on your truck.

Your head light switch has a bunch of wires going to it from a "smart junction box". Each wire going to the smart junction box has a function, and all the switch does is ground these various wires to tell the smart box what to do.

To tell the smart box to turn the lowbeams on, the headlight switch grounds the yellow/blue to turn the headlights on, and then the multi-function switch does not ground anything, and the lowbeams should be on(to turn the high beams on, the multi-function switch grounds the white/orange).

Then the smart junction box has outputs. There are fuses for the lowbeams in the smart junction box, F7 and F8, both 10 amp. Then inside the box it goes to a solid state switch, which then puts power on the brown/blue(left lowbeam) and the blue/green(right lowbeam).

They show the smart junction box over by the pass side hood hinge area.

 

Wow very cool Dave! Thanks for all the info and looking at the wiring diagram. I should have some time this weekend to look at the smart junction box. This junction box isn't the same as the fuse panel correct? It doesn't sound like it as the fuses I looked at are on passenger side by door hinge area.

 

I am not sure exactly what it looks like, but according to the diagrams the smart junction box does have fuses, so it may look like a fuse box on top, with all the brains and controls underneath inside. The best scenario I can think of is yes, you do find the box, it has fuses, and they are blown.