Both headlights out at same time

I have a 2001 Honda Civic and both the headlights have gone out. I
checked the fuses under the hood (there is one for each) and they look
good. I replaced one of the bulbs... nothing. Everything else in the
electrical system seems to be working ok.

Does anyone have any idea what to check next?

Thanks

 

Headlight relay?

 

Where is the headlight relay? I only have the owner's manual and it
doesn't seem to say.

 

Not sure-- you'll need someone above my pay grade.. Some cars have them in
the underhood fuse box, or it maybe integrated into the h/l switch. Also,
the switch itself may be the culprit.

 

Hi,
On Japanese cars, if one side burns out and fuse goes both will go out.
Check fuses with meter(visual check is no good) and check both side
bulbs with meter.

 

wrote in @v3g2000hsc.googlegroups.com:

If one of the individual lamp fuses blows, the other side is **NOT**
affected, so that's not your problem.

Do the headlamps work if you pull the headlamp switch stalk towards
yourself? (Flashes high beams.) What about if you turn the the stalk to the
high-beam setting?

Don't ignore the obvious here: the possibility that both of your low-beam
filaments have failed at the same time. Buy a new bulb (even a cheap one),
swap it in and see if it works.

You actually have a third, 100A fuse, under the hood. This protects both
sides of the headlamp circuit. See if that's blown. You'll need a test lamp
or multimeter to check that one.

 

don't know about new models, but my 1992 civic doesn't have a
headlight relay. (i put one in, along with decently large gauge
wiring. significant improvement, highly recommended. thanks to stern
lighting for advice).

 

Yes, unlikely as it sems; that happened to me. and i'm the kind of guy
who checks the reflection in the back of the car in front of me at
night to make sure they're both working, so it's not like one burned
out and the other one a month later.