on My honda civic 2012, my low beam lights are not working, I thought my blub is fused or something. However, when I examine in detail it was okay.

When I turn on my high beam all 4 bulbs turn on. It only when i turn on only low beam those don't turn on

Is there a simple fix or should I check with mechanic?

  • Your car should have four headlight bulbs, with a fuse for each one. Two are high beams, and two are low beams. I would recommend checking the fuses for each bulb, and then removing and inspecting the low beam bulbs to see if the fillament is broken, by either visual inspection, or checking continuity with a multi-meter. It's strange that both low beams would burn out simultaniously though, making me wonder if it's a problem with the switch, a relay, etc. Because of this, I'd recommend checking all the fuses. Nov 15, 2019 at 18:13
  • Bulb is not burned out... When i turn hight beam all the four bulbs turn on Nov 16, 2019 at 0:30

1 Answer 1


From a circuit diagram I have found on the internet (if it is correct for your car), it looks like there is a pair of headlight relays in a fuse box under the hood. These relays switch the +12V to the headlights. It looks to me that if one of the relays fails, then the +12 will find its way through all 4 bulbs making them all light when switched to high beam.

See if there are other identical relays that you can swap out to see if the fault goes.


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