I'm having a serious issue on my 1994 v8 Slt Dakota, at the most inconvenient and dangerous times my headlights just turn off when I'm driving, when it first started happening i turned my hi-beams on and my lights would stay on, but now it cuts out either way, i noticed the headlight switch was EXTREMELY hot after being on but my fuses are fine, oddly enough they WILL stay on if i continuously hold the hi-beam switch? And its ONLY my headlights, running lights and brake lights and all still work fine. If anyone can suggest ANYTHING, it would be extremely helpful, my job requires my to drive mostly at night and not only does it happen at any given time but its very dangerous, not to mention illegal... Thank you so much in advanced for any bit of information.

 

check for bare wires on the headlights, might be a short, also check ground, you are drawing a ton of current if the switch gets that hot

 

I don't actually know why your headlight circuit is cutting out.

However, I do have a similar experience on a Ford chassis'ed motorhome. It was built with those old fashioned small rectangular 4 lamp headlights. When whoever designed the system for the motorhome did their job (or really didn't!) they ran the wiring directly out of the switch, through a floor switch, and then to the various headlamps. NO RELAYS!

This puts a terrible load on the dash mounted headlight switch, it's not meant to handle all that amperage--the switch was overheating and then just cutting out, like yours is doing.

The answer was to rewire the whole thing with some new heavier wiring and relays, so that actual lamp voltage came from the battery and didn't actually go through the dash switch.

My guess, with all the heat at the dash switch, is that something similar is happening. Perhaps the contacts for the relay are burned or oxidized, causing a lot or resistance--higher resistance means more amperage to make the connection in the relay and more heat. Not 100% sure this is right, but it gives you something to consider.

 

I don't have the diagrams for the 1994, but my 1988 is like Brian_In_Tucson said - straight off the headlight switch.

It can also be due to the MFS or dimmer switch (depending on the design yours uses - MFS I think, but it may be like the 1988 and the dimmer be a different switch) failing.

In any case - time to grab the wiring diagram, start chasing the wiring, and checking for where the voltage stops.

I'd lay more odds on the MFS/dimmer switch myself, although the "flash to pass" has a separate run for power, so it COULD be the headlight switch failing.

When you replace them both *grins* be sure to do like Brian_In_Tucson said, and add relays.

RwP

 

I checked all the fuses/relays once again and made sure my connections at the switch itself was secure and i pulled the **** and it had the same issue, yet this time i examined the headlight switch while it was on and it immediately started sizzling/smoking from the connector. But Im just gonna have to do what you guys say and chase down the wiring, at this point im just having a difficult time finding a diagram that has all 9 headlight switch wires to make it a little easier haha. But thank you all so much, its time for me to hunt some faulty wiring!

 

Time to buy the factory service manual (Ebay shows several vendors under $10) and the wiring schematics (that may take the more expensive manuals).

RwP