Hi guys,

I have a recurring issue with my headlights. Sometimes while driving my low beams will just go out. When I cycle the switch on and off they come back on, sometimes they go right back out other times they stay on. This only happens with the low beams, and doesn't seem to matter whether the fog lights are on or off. The problem is only with the low beams. The high beams always work. *Also the passenger side headlight bulb keeps prematurely burning out. Not in days, but usually in a couple months. *They are just silverstar standard wattage bulbs. I'm not using any high draw bulbs or anything.*

Orriginally I thought the problem was due to the snow plow wiring harness. It's a Curtis sno pro 3000, if it matters. The way this harness is set up at the lights is by plugging the oem plug into the harness plug, and plugging the harness' plug back onto the headlight bulb. There is a toggle switch on the dash that switches the vehicle lights and the plow lights on and off. To clarify there is a two position switch on the dash, one position is "vehicle lights" and the other is "plow lights".*

When I first started having this issue I figured it was a problem with the plow light harness or the switch, so durring the spring and the summer I simply replaced the oem plug onto the headlight, and took the plow light harness out of the picture, problem solved. I didn't have the intermittent light issue again until recently. So with the plow harness and switch removed from the equation I am back to the oem plug, switch, or harness being the problem.*

I noticed last time I replaced the headlight bulbs that the inside of the connector on the passenger side bulb had some green corrosion on the contacts and on the pin contacts of the bulb I cleaned it thoroughly, and used a little di-electric grease on the plug before reinstalling the new bulbs.*

Now with Winter coming, an the need to get the plow harness back in the picture again, I am pressed to fix this little problem.*

Now the questions:

when I click on the high beams I can hear a relay clicking on and off, in the owners manual I can find a listing for the high beam relay, however I don't find one for the low beams. Is there any component in the low beam circuit that would shut down the lights to protect it? The fuse for the low beams is good, and I replaced it anyway just to eliminate it and the problem persists.*

So is there anything else in the low beam circuit that would cause this?

Has anyone experienced anything similar with intermittent lights?

Should I just replace the switch on the dash to eliminate that as being part of the the problem? Since when the lights go out and I cycle the switch I usually get my lights back.*

Does the fact that I found the corrosion inside the headlight plug indicate anything beside a moisture issue? I believe the Di-electric grease has solved that issue.*

Is there any type of component in the circuit that works as a sensor to prevent overload, or to detect voltage problems (similar to the indicators you get on some vehicles when you replace a filiment bulb with an LED, the sensor "thinks" there is a bad bulb)? Is there anything like that in play here?

I'm grasping at straws a little here because I don't want to take it to my dealer because I think they will just blame the plow installer, even though there are no splices into the OEM light harness anywhere.*
By the same token I don't want to go back to the plow installer, and have him blame it on any of the OEM stuff.

Thanks for reading, I know it was a bit long winded, but so many posts are answered with more questions, so I tried to include as much info as I could.*

Thanks for any help
~~~ Chris.

As a side note I realize I have about zero posts here and some will consider me just a lurker, or something. I generally don't bother to post on any of the forums I belong to just to get my post count up. I really only post if there is something constructive to add to a thread, and since this is my first diesel, (not first Ford though) I haven't had anything constructive to add to the many threads I've read here on this forum. Thanks for your help and consideration *

 

Yes, the multi-function switch on the steering column. That switch is what turns off the low beams when you click on the high beams. A bad connection in that switch, or the wiring up to it and back, could be the problem.

Good job on a well worded question. We get too many one sentence questions around here.

 

Do you have Daytime Running Lights? They have a relay and controls associated with the low beam circuit. This question is just to eliminate a possibility.

 

No daytime running lights, and the fog lights are oem, on it when it was bought

I hadn't considered the steering column multi funtion switch, I was leaning toward the dash switch, on off switch. Am I off base? Is the steering column switch more or less likely?

 

thank you for the compliment. I know it's important to be clear and give as much info as possible.

What do you think is my next step, is there any way to test this switch at a harness plug (for shorts or resistance)

maybe I'll just replace both switches and eliminate the possibilities.... Unsure which route to take. (story of my life )

 

I think you can test the headlight switch easily enough. Pull it out and test it with a VOM. Wiggle stuff around and see if you can see an intermittent connection.

On the multi-function, there is a butt load of stuff that goes through that switch. Most guys just put in a new one and say a little prayer. Neither switch is very expensive.

 

Alright that'll be the plan then. I'll check back in when I get it done and post the results. Thanks for the help guys. I've spent a boatload on my two trucks lately doing regular maintainance and am low on dough. I appreciate the help

 

I think this is the switch:
www.partsguyed.com

 

Thank you for the part look up.

 

Hey look what I just found in a list of tsb's that "Senix" steered me towards in a different thread I started. I bet this is my problem, because it's exactly what is happening to me. More or less .
I'll have to look into this. Glad I hadn't ordered any switches yet

Headlights inoperative on snow plow equipped trucks:
On 2008 F-SuperDuty trucks the smart junction (fuse) box--SJB; monitors circuits for excessive current loads to determine if a short circuit occurs. The SJB may interpret switching from factory headlights to plow frame lights as a short and will shut down the headlight power. The SJB can be reprogrammed to prevent this from occuring. Broadcast Message 6987, TSB 07-9-1.

 

Interesting. So now what's the plan? Visit the dealer for programming?

 

X2 on the switch. I have the switch with the fog light option. I have noticed that issue, as well as the fog lights coming on by themselves " When the headlights are on" When I hit a severe bump in the road. It seems as if the switches moves easily both headlights and foglights.

Maybe that is why your are burning your headlamps out prematurely, the arching in the switching is passsing the volatge volicity difference to the bulbs, causing arching " High amperage" in the bulb socket, making the bulbs loose their life to soon.

Keep us updated when you replace the switch, if it cures the problem


Slim_Dowg

 

I just got of the phone with the service guy at the dealership. He seemed at least open to the suggestion. Asked me if I wanted to bring it in tomorrow and they'd check it out for me, he also offered to replace either of the 2 switches for me if they needed to. I've spent a ****load (pardon the expression) of money there recently on service, and some accessories, like thousands $$$$. So I at least believe they'll bend for me a little. Either that or they smell a sucker. Just kidding. Joe's a good guy, and slowly convincing me that all dealer service departments aren't crooks. I'll let ya know what happens.

 

could very well be that. He seemed like he wanted to just try the switch first and take it from there. I just need this fixed so I don't need to worry about it. Plow season is banging on my door, and I wanna answer...

 

Generally, most service depts treat you differently, when they see that you are mechanically skilled, and know your vehicle better than they do at times...lol


Slim_Dowg