My truck didn't ship with factory bumper fog lamps. So I bought the knock off factory lights and bezels for the bumper. And bought a factory knock off replacement headlamp lamp switch that includes the fog lamp switch. When it came in, I confirmed that the pull out fog function causes the two pin connector to short the pins together.

So I pull out my factory switch, expecting no pigtail harness. Surprise, there is one and its connected to the switch?! So I get the switch out, and compare it to the one with fog lamp function. They look pretty much identical, BUT there is a blue plastic insert that won't allow the harness to plug in. So I pull the harness from the 1999 that had factory fog lights... same problem.

What is going on here? I put some needle nose pliers in there to see if I could pull that blue plastic out - it must be glued in.... what the heck...



Left side, factory w/o fog lights. On right, aftermarket knock off with pull out fog lights.

 

If you're sure it will work once the blue tab is out, you could drill into it with really tinny bit and then dig pieces out with a pick. May be more difficult if its loaded with adhesive tho.

 

Ok, figured it out. The new switch they sent me, must have been a return. Because that blue piece is actually part of the harness plug ! I yanked it really hard and it came out. Then I stuffed the spare harness plug I had in there to make sure it fits, then pulled it out... to my surprise, a new blue piece inside the switch!

So that mystery is over... but not solved, is why my original mopar one actually has that port and pins AND harness- but no pull out fog lamp feature. Guess I'll scan the factory manual to see if there is any difference, I can't imagine them using those wires for something else....

 

There isn't. A lot of times Mopar used the same things across the board as it was cheaper. When I went to install cab lights on a buddies truck (97 1500) the harness was already there.

 

I found the factory fog lamp harness under radiator, or what I believe to be the harness - correct place, same color wires as my backup harness, but the connector is corroded - really bad like nonexistent. So I just cut that connector off and bare the red and blue wires for testing.

I installed the new switch, tested to make sure it ran the parking/head lights and interior lights.... All good. Look in the PDC, looks like the fuse is installed in the fog lamp socket - but no relay. So I grab a relay and push it in and out a few times to make sure its making contact. Put the parking lights on, and pull the **** - the indicator that the foglamps are energized lights up. Slide under the truck and try my test lamp between red and blue... nothing. Clamp on the blue, spike into ground, nothing. Clamp on the red, spike into ground - and the test lamp lights up strong. Ok, thinking Ive got it made now - just a bad ground - like usual on this truck. So I push the **** in (turn off the fog lamp), slide under the truck, and I've still got power on the red wire?! Ok, pull the relay, check again - still have power... what the hell is going on here...

Got dark, and put some black tape over the red wire... more testing tomorrow.... thinking this is going to have to wait till after I get this thing inspected.

 

Got the right diagram up.... Am I reading this correct? Are the lamps really hot all the time, and they just switch the blue wire to ground with that relay? That would explain why I see power on that red line all the time.
Not what I thought would be happening, but MoPar's wiring choices are always not what I'd expect.

Tomorrow I need to see if that blue wire is getting grounded when I pull out that headlamp ****. Wouldn't surprise me if I have another bad ground though.

 

what the heck is the site staring out the word k n o b ?

 

Sometimes, the words the auto-censor takes offense at, truly astounds me........ and this site isn't NEARLY as bad as some others I have been on......

 

Couldn't get the blue wire to go to ground with my tests, so I guess I"ll need to dig into it later and find out what is going on. My initial guess, bad ground.
MoPar wiring... sucks.

 

I think the headlights actually have to be on, and on low beam for the fogs to come on.