Help! Fogs NOT working...

[96max2fast]

Problem Solved... The previous owner ran the wire from the stock fog switch separately... he also inserted another in-line fuse and it was BLOWN... That was the problem... Switched it and it works perfectly... After all the searching... I'm an electrical pro now!

Thanks to all.........

I have a 97 Expedition XLT 4.6L and I recently installed HID's in the fog lights. 1 was flickering for some reason (perhaps a defect with the ballasts) but then it worked well for a few days. Now, neither of the Fog Lights work. I turn on the switch but they don't light up. The FOG fuse under the steering wheel appears to be good. I tried to put my original bulbs back in and they don't light up either!

What could it be?
Is there a specific relay that controls the fog lights?

Please help!

Waldemar

 

[Thermo]

96max, I would venture to guess that you have blown the fuse for the fog lights. Keep in mind that the factory fog light fuses is only a 15 amp fuse and when you turn on the fog lights, each ballast for the HID bulbs pulls in the neighborhood of 20 amps (40 amps total). Normally the fuse will handle this for a little bit, but over time, the fuse will weaken and finally fail. If that is not blown, then I would be looking at the fog lamp relay. Again, this relay is only rated for 20 amps and you are almost doubling that when you turn on the fog lamps. So, it is possible the relay gave up the ghost.

 

[96max2fast]

96max, I would venture to guess that you have blown the fuse for the fog lights. Keep in mind that the factory fog light fuses is only a 15 amp fuse and when you turn on the fog lights, each ballast for the HID bulbs pulls in the neighborhood of 20 amps (40 amps total). Normally the fuse will handle this for a little bit, but over time, the fuse will weaken and finally fail. If that is not blown, then I would be looking at the fog lamp relay. Again, this relay is only rated for 20 amps and you are almost doubling that when you turn on the fog lamps. So, it is possible the relay gave up the ghost.

Makes sense. The fuse is still good, so it appears. Which fuse controls the fogs?

 

[Thermo]

96max, fuse #9 in the engine bay fuse box is for the fog lights. if in doubt, swap the fuse with an identical fuse (same rating) and see if the fog lights work then. As for the relay, not sure which one it is right off the top of my head as my Chiltons book doesn't state which relay is which.

 

[GAINMOB]

check the ballast...if you got them from ebay...they could just be a bad set...borrow ballasts from someone who has HIDs and see if they work...happened to me once...emailed the comp and they sent new ballasts...was good to go

 

[Thermo]

Freeway, he said he went back to the standard bulbs and they didn't work either. while I am not saying that the ballasts are good, there is atleast 1 problem that is inside the truck.

 

[GAINMOB]

my bad...i have a tendacy not to read them all the way through when theyre long...i mustve skip'd that part....

 

[dcarr]

another quick way to test ballast is run 12v straight from batt. idk anyone else around me with hids.

 

[Thermo]

dcarr, I have HIDs in my Jag (both headlights-OEM and fogs-aftermarket). All the 12 VDC test directly to the ballast tells you is that the problem is either the ballast or the bulb, but not which one of the two it is. The only way to prove that is to either use a brand new bulb with an old ballast or to measure the voltage coming out of the ballast. I don't recommend the voltage check as the ballasts can and DO!!!! output 23,000 VOLTS!!!!!!!! Very few multimeters are capable of handling that kind of voltage. Now, the 23,000 volts is only for a few seconds, but I will tell you what, that voltage will drop kick your butt pretty good. Not that I have ever taken voltages like that or higher myself (looks away innocently).

If you have any questions, just ask. I can go into all sorts of detail and probably way deeper than you truely want to go.

 

[96max2fast]

Problem Solved... The previous owner ran the wire from the stock fog switch separately... he also inserted another in-line fuse and it was BLOWN... That was the problem... Switched it and it works perfectly... After all the searching... I'm an electrical pro now, so I could probably help you out now...

Thanks to all.........