Headlight Switch

[TLadd]

Riding down the street in my W-350 and I hit a bump and the headlights turned off all by themselves. I investigated the problem and found that the previous owner had run two wires of the headlight switch (I believe one was black and the other was a light pink) to a relay. The headlight switch was melted around a few contacts. The switch has been replaced because the previous owner had the kit to fix the headlights that he got from the dealer. Is this common to burn out a switch and plug even though the headlights have a relay attached? How long does this setup usually last?

 

[TLadd]

I'm in the process of soldering a new plug into the wiring harness and once that is done I will install a new switch. Any other suggestions while I've got everything torn apart?

 

[dpuckett]

Normally, if the relay is run off the right wire, and all the connections are good, the switches wont melt again. I have had butt connected wiring get hot and cause switch metldowns. Solder gun and solder fixed that.



Did the P. O. get all the wires back where they belonged? Is the wiring heavy enough to carry the load? The 350s tend to go through switches faster than the 250s due to the extra lights.



Daniel

 

[Moab4x4]

Per a recommendation on TDR, I also put a relay on the parking light wire. Had to snip that wire(don't remember the color. . brown with a yellow stripe??) shortly after the switch and install the relay there. I put my headlight high and low beam relays under the hood.

Your HL relay must be before the dimmer switch.

My switch wasn't melted down yet, but was discolored.

That is not a roomy fun place to work on that harness, my back hurts just thinking about soldering in a switch plug.

good luck

Ken

 

[TLadd]

That's the other thing, my parking lights are the lights that don't work when you pull the knob out one position, but they do work when you pull the knob out all the way with the headlights.

 

[Moab4x4]

Is that the switch or the wiring I wonder? I hear the parking (dash, etc) lights don't draw that much juice unless you have the cab marker lights, but a trailer especially with markers could really toast that part of the connector. I added the relay for two reasons, one was the afore mentioned issue, but the fun one was the keyless entry / alarm system I installed will flash the parking lights with that relay installed. Either the HL switch or the alarm box close the relay.
More work that it was worth, but the keyless entry is handy and kind of fun on an older truck. Turns a few heads. :-laf
I can look up that wire color if you need it. FSM is out in the shop.
Ken

 

[csnider]

If the parking lights only go on with the switch all the way out then the switch is bad. . They go bad fairly easy. especially aftermarket ones. I bought a Napa switch and it died really fast. . I finally broke down and bought the dealer kit (with relay and new wires and socket) and so far so good . . the switch feels much better than the Napa junker I bought. . Your experience may be different but as hot as the switch and socket get . there is probably a chance for a electrical fire in there so get the best components you can. . My orig socket was melted pretty bad in a few places... .