87 and 85 are grounds. With the relay pulled, headlights and foglights both on, both pins should should continuity to ground.

 

i checked continuity to ground on both 87 and 85 and both had continuity to ground with the relay pulled with the fogs and low beams on.

I get constant voltage to 30 and 86 with the relay pulled regardless of key and switch position (even with light off and key out of ignition).

fog lights still do not work. I even went to local ports store and picked up a new headlamp switch. I once again checked both wires at the fog lamps and both get 12V.

I once again checked continuity on both fog lamp bulbs and both have continuity. Once again I swapped relays (now tired 3 different relays).

any other thoughts on why my fog do not work?

- Dan M

 

Plug a wire into pin 30, (preferably with an inline fuse....) and run it to a good ground, and see if the fog lights come on.

 

HeyYou - are you saying to pull the relay out of the PDC and run a wire with a fuse from pin 30 to a good ground. Then turn on the fog lights? does it matter fuse size? 15 amp?

- Dan M

 

Yep, exactly what I am saying. 15 amp fuse would be good.

 

I ran a jumper wire with a 15 amp inline fuse to a known good ground (same as battery uses).

even with the fog lights off, the fog light indicator on the switch in cab was on. the fog lights still don't work though

- Dan M

 

It's almost like the 12 volt to the lights isn't enough to power the bulbs. I'm at a loss, anyone else have any suggestions?

- Dan M

 

That is just odd...... Do you get 12 volts at pin 30 on the relay? If so, grounding it SHOULD have turned on the lights.........

If you weren't about 600 miles away..... I would be tempted to come have a look.

This is an exercise I am going to get to go thru soon too though, as my Fogs don't work either, and the bulbs look good. I had thought the indicator on the switch worked correctly, but, looking at it, I begin to wonder if I didn't push the wrong button. (OD disable is right next to it, and has the same style light)

Raining here today.... and I have an intake to address, so, this bit is going to have to wait for a few.

 

Turns out, I found another break in the wiring for the lights themselves but no break in the coating. Very odd, never seen that before. I repaired that and ta-da! Fog lights work.

even though i was getting steady voltage at the fogs themselves, it wasn't enough to power on the lights. perhaps it was a resistance issue. i didn't bother to check resistance before i repaird the break.

Thanks for all the help.

- Dan M

 

EXCELLENT!!!!

Yeah, the wires can fatigue, and break, but, the insulation looks fine. Doesn't happen real often, but, when it does, can be a real bear to find.

Glad ya got it working!