Both Headlights Out

Hi,

The headlights on my ’99 went out the other day. I changed both bulbs and all seemed fine for several days until tonight. Now the head lights are out again. The dash lights work and I can flash the brights but other than that both the low and the high beams are out. Where should I start looking?

Thanks in advance.

 

On your previous set of bulbs were both high and low beams out? On either set did they go out at the same time? Are you running over wattage bulbs?

The fact that you can flash your lights (flashing usually runs the high and low filament at the same time) but not run on low beam or high beam and are experiencing this on both sides indicates it is not a bulb problem or a wiring/fuse problem. To me it sounds like your headlight switch needs to be replaced.

 

I would agree, if they "flash" then they should work, but I think its just the high beams that flash.

any way, check the FEM for test procedure and test your headlight switch in the steering column, its probably gone bad

 

Thanks I’l check out the switch.
I’ve discovered that the problem is intermittent and that the lights will go out for a second when I hit a bump. I did look for loose wires including a loose ground strap today but found nothing. Of course when I was testing in my driveway they stayed on. Tonight I tried again and they were out so I flashed the brights and they came on and stayed on.

 

I’ve replaced the switch (and it’s not a cheap part for sure) but the problem still remains. The only way I can duplicate it in the driveway is to drop the hood really hard which of course makes it impossible to then check anything.
My next thought would be to replace the relay except that it is in so tight that I can’t pull it out. I would guess that means it’s not so loose that it’s loosing connection.
Any other thoughts about what might be causing the headlights to shut off randomly?

 

Check all your wires for breaks or pinches

 

Thanks for the quick answer Bellassaiw10,
I have looked for breaks, pinches, loose grounds, corroded connectors and double checked the wattage on the headlamp bulbs. I can’t see anything wrong. Nothing is more fun to track down than an intermittent problem.

 

Tracking down intermittent electrical problems is frustrating. When you say you drop the hood really hard to reproduce the problem, what exactly do you mean? The headlights don't work, you drop the hood and they flash? Or they do work, you drop the hood and they flash off? An intermitant problem like that is likely at a switch with normal wear and tear, so I'd also check the relay, they can fail, they don't have to be lose. Can you get a small screw driver or something else to pry it out? Otherwise everything else should just be wire, which shouldn't fail unless they overheated, pulled loose or otherwise were tampered with. Do you have any sign of rodents? What about just tapping on the relay to see if that reproduces the problem?

 

check your relays. i believe we have a headlight relay in the engine compartment. should be a simple 5 terminal relay. if it doesn't work, it was only 14 bucks or so

 

Did you resolve this?
The same thing happened tonight in my '02.
On low beam I have only side markers, high beams work just fine.

 

Did you try changing the bulbs? It's not uncommon for the low beams to go out simultaneously. You could check the filaments if you know what to look for and don't want to buy new bulbs.

 

Yeah the bulbs were good.
This evening on the way home as I was turning left they just miraculously came back on...
They came on as my switch arm clicked back to nuetral after the turn was complete. I'm thinking the switch is my problem.

 

that's a very good indication. if you're feeling brave, or just have the replacement in hand, you can take the original apart and probably just clean the contacts. I did that with my passenger power window switch since it didn't want to control it's window. took it apart, cleaned the contacts, put it back together, and voala it works again.

 

I’m opening this thread back up because my problem still exists. It seemed to go away for a while (plus the truck was in the shop after someone rear ended her). Now it’s back with a vengeance. I’ve replaced both headlight bulbs, the switch, and the relay. The lights work for a little while then quit and I have to hold the switch in the flash position (that makes turns fun) since neither low or high beams work otherwise.
Any thoughts and help are much appreciated.

 

I replaced the entire stem on the steering column and that solved it for me.

 

I wish it did for me. That’s what I meant by when I wrote that I replaced the switch. Sorry if that wasn’t clear.

 

It was very obvious for me, I had a melted wire.
Sorry about your luck

 

Maybe it's the module that the switch plugs into?

 

That’s a good thought but the module looked like it was in perfect shape. I really hate the idea of replacing that just to find out that it, too is not the problem.
It seems the only way to make them work is to dangle a test light in front of them.