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Dodge Ram b3500 Van - why are the headlights going out?

Hey all! I have a 1999 Dodge Ram b3500. Had her for a couple years now, and she needs some regular maintenance, but she’s been doing pretty good. Took her to Austin from Jersey and back last year. In the last couple months I’ve had a problem crop up on long trips though, and my mechanic doesn’t seem to be able to figure it out. The last couple times I’ve taken it on long trips, I’ve been having a problem with the headlights. They’ll go out suddenly. I can fiddle with the knob a little and get them to go on again, but they’ll do it with increasing frequency as I continue to drive, up to several times a minute. Twice now I’ve had it happen, in heavy fog, at night. My hazards still come on just fine though. Then I turn my brights on for a minute, turn them off and the lights are fine. Could it be a loose connection somewhere? Please help!

Do you have daytime running lights? At this point it looks like it might be the headlight relay getting hot and breaking down.

There are no daytime running lights. How could I tell if it was the headlight relay? Is there any easy way to check that or stop it from going out? Thank you!

Most likely the circuit breaker is overheating, cooling down again and overheating again. The brights are on a different circuit. Why it is doing it could be a switch going south, corroded bulb sockets, bad wiring someplace in the circuit etc. I’d suspect the switch. Relays should be just interchangeable with others in the relay center so easy swap one out to test it.

I agree wtih Bing and suspect a failing switch. Cars used to have the circuit breaker built into the headlight switch. I don’t know if yours does or not. The breaker used is a thermal breaker and when they get weak you will experience behavior exactly like what you’re getting. Of course there could be an actual overload in the system causing it too. The best thing would be to check the amp draw on the circuit before replacing the switch.

Your wiring goes straight from the headlight switch into the dimmer switch before it reaches the headlights, so now it could be the headlight switch, the dimmer switch or the relay. Good luck with troubleshooting.

I have a 1997 b1500. It was doing the same thing. My brights are dimmer than the dims on most vehicles now days. So I cut the “bright” wire close to the headlight on each side and wired it direct to the battery with an in-line fuse and a switch added inside. Now I have a separate switch for my headlights and my driving/park lights are still fine. When I looked at my headlight sockets the connectors were rusting inside so I suspect that was the overall problem. My hillbilly solution works for me as I don’t care if everything looks stock in a piece of crap van that is headed for a upullit after I drive it into the ground. And it’s getting closer to that than I’d like.