# Headlight sometimes works

**URL:** <https://community.cartalk.com/t/headlight-sometimes-works/72456>\
**Category:** Maintenance/Repairs\
**Created:** [May 16, 2012, 7:19am UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456 "2012-05-16T07:19:46Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Lee\_H](https://avatars.discourse-cdn.com/v4/letter/l/73ab20/32.png) [@Lee\_H](https://community.cartalk.com/u/Lee_H)\
**Post date:** [May 16, 2012, 7:19am UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/1 "2012-05-16T07:19:46Z")

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My '06 Pontiac Vibe sometimes has one headlight out. When it’s on as a daytime light, or on normally, the right headlight is not working. As a high-beam, it comes back on. It did this for a few days, then came back to normal after I hit a hard bump. Now it’s back out again. It sure sounds like a loose wire to me, but I can’t find it by jiggling wires behind the light assembly. Any suggestions?

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**Author:** ![MG-McAnick](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mg-mcanick/32/188_2.png) [@MG-McAnick](https://community.cartalk.com/u/MG-McAnick)\
**Post date:** [May 16, 2012, 8:19am UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/2 "2012-05-16T08:19:59Z")

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You need a new bulb.

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**Author:** ![SteveF](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/stevef/32/2_2.png) [@SteveF](https://community.cartalk.com/u/SteveF)\
**Post date:** [May 16, 2012, 12:54pm UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/3 "2012-05-16T12:54:09Z")

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Verify the bulb by swapping left & right.

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**Author:** ![BustedKnuckles](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bustedknuckles/32/25_2.png) [@BustedKnuckles](https://community.cartalk.com/u/BustedKnuckles)\
**Post date:** [May 16, 2012, 2:20pm UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/4 "2012-05-16T14:20:36Z")

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The bump probably allowed the broken filament to jump back into position and reconnect itself with a microweld. But this is a temp fix, and it will break again soon. The reason the high beam still works is because the bulb has two separate filaments, one for low beam and one for high beam. The low beam filament is the one that broken, fixed itself with a very temporary micro-weld, and will fail again very soon.

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**Author:** ![Lee\_H](https://avatars.discourse-cdn.com/v4/letter/l/73ab20/32.png) [@Lee\_H](https://community.cartalk.com/u/Lee_H)\
**Post date:** [May 18, 2012, 6:45pm UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/5 "2012-05-18T18:45:33Z")

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Thank you, I will get on that.

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**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\
**Post date:** [May 19, 2012, 12:22am UTC](https://community.cartalk.com/t/headlight-sometimes-works/72456/6 "2012-05-19T00:22:21Z")

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I think Busted is right except that I think the filiment is jut “hung up” at the break rather than having microwelded itself together. Tungsten’s melting point is over 6000 degrees F.

I’ve seen bulbs do this. You have a quartz halogen bulb, which is a regular tungsten filament sealed in halogen gas in a fused quartz bulb. The halogen gas allows the tungsten to reach high temperatures without burning up. The fused quartz withstands the high temperatures without breaking.

Congratulations. Best case, the plug to the bulb has come loose. Worst case, you just need a new bulb.