I installed the crystal clear fog lights in my 98' f150 that did not have them from the factory. I plugged them in and pulled the switch out, and they dont come on... Am I missing something?

 

Using the factory ends on the truck, you plugged in fog lamps, or did you install a complete kit ?

Few things come to mind, if you never had fog lamps installed..
1. The switch that was installed, is this a '98-'99 switch, or a '00-'03 switch
1.1. The switches are different, and depending on which MY switch was installed, is depending on what it is trying to do to the factory harness ( more on the harness later ).
1.2. The '98-'99 fog lamp switch, switches ground to the fog lamp relay coil
1.2.1. https://www.f150online.com/galleries...028-149973.gif
1.3. The '00-'03 fog lamp switch, switches +12 V to the fog lamp relay coil
1.3.1. https://www.f150online.com/galleries...028-152065.jpg

2. Is this an illuminated switch ? I am not sure of the '98-'99 MY fog lamps have an illuminated icon on them, like the newer MYs do.
2.1. If the fog lamp icon is not illuminated when you pull the switch out, for the fog lamps, while in the low headlamp position, then it seems that Central Junction Box Fuse #27 ( 5A ) is missing.
2.2. If the fog lamp icon illuminates, then it is time to check what is going on with the fog lamp relay.

3. Fog lamp relay ( in the battery junction box ) will power the fog lamps via the Battery Junction Box fuse #9 ( 15A ).
3.1. If you short pins 3 & 4 ( this is different then the '00-'03 MYs ) do the fog lamps work ?
3.1.1. This would be providing power from BJB Fuse #9 to the fog lamps, and tell you if the wiring harness is correct from the BJB to the fog lamps.

4. When the main headlamp switch is in the on position, with the low beams on, meter across pins 1 & 2, you should have +12V ( DC setting on the meter ).
4.1. If you do not get +12V across pins 1&2, the fog lamp switch is not sending ground to the fog lamp relay coil.
4.2. Check with a different ground ( like the battery terminal ) the voltage at pin 1.
4.2.1. If you do not have +12 v on pin #1, then either the fuse noted above ( CJB Fuse #27, 5A ) is either bad, or it does not have the wiring harness to the BJB box. This would not be a shock, as the harness might not be complete in the truck. Not uncommon in '98 & '99 MY trucks.
4.3. If you have +12v on pin #1 using a different ground, either the wrong MY switch is installed, or the harness is not complete to the BJB, for switching the ground side fo the relay coil

Those are the items I can think of off the top of my head at the moment.

 

hmm ill check

 

What color wire runs to the fog lights up in the switch? If I can find that out, I think i can make them work untill I get a $120 switch

 

Found it, got it working now, thanks!

 

Want to let others in on what the solution was ?

Another member might have the same problem someday, and a search would show this thread, and no answer is in the thread.

Thanks

 

Very good point. I connected the solid yellow wire to a ground, and then the white wire with a black stripe to the solid brown wire. Now doing it this way, the fog lights come on with the headlights, high and low beam, but you cant shut them off. I will soon get a new switch made for fog lights, but untill then, this will work.