My wife's 2001 Chevy Tahoe low beam head lights stopped working. She started her vehicle and they just wouldn't turn on, high beams work, daytime running lights work also. I've checked all fuses, relays, etc. All have power. I don't think that both low beam lights could die at the same time, but I plan on buying new ones today just in case. What would you do if that doesn't work? thanx

This is usually caused by a failed front control module as this unit controls the lighting on the vehicle!
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airbag reset tool

HEADLIGHTS NOT WORKING

It can be faulty headlight switch or issue with its wiring. Or its faulty head light fuse.

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To troubleshoot the issue i suggest you few help links with appropriate solution. So you can follow the test and confirm what exact problem is there in your case of headlights not working:-----

Click the link below: -----

All headlights not working?

http://repairhelpcenter.blogspot.com/2012/01/all-headlights-not-working.html

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• Working of Headlight switch?
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• Both headlight bulbs blow together?

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• Car headlight bulbs don't last long?

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2007 Dodge Caliber: Low Beam Headlight Not working

http://technoanswers.blogspot.in/2012/06/2007-dodge-caliber-low-beam-headlight.html

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2003 Toyota Camry: Headlights Work Intermittently?

http://technoanswers.blogspot.in/2012/04/2003-toyota-camry-headlights-work.html

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Chevy Tahoe: Low Beam Lamps are not working?

http://technoanswers.blogspot.in/2012/04/chevy-tahoe-low-beam-lamps-are-not.html

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2001 Chevrolet Tahoe: Headlights not coming ON?

http://technoanswers.blogspot.in/2012/04/2001-chevrolet-tahoe-headlights-not.html

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2004 Dodge Ram: High Beam Light is DIM?

http://technoanswers.blogspot.in/2012/04/2004-dodge-ram-high-beam-light-is-dim.html

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2001 Chevrolet Tahoe: Both Low Beam Lamps Not Working?

http://technoanswers.blogspot.in/2012/04/2001-chevrolet-tahoe-both-low-beam.html

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Low beam headlights Modification?

http://schematicsdiagram.blogspot.in/2012/04/low-beam-headlights-modification.html

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How to Replace a Headlight

http://schematicsdiagram.blogspot.com/2011/08/how-to-replace-headlight.html

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How to Replace a Headlight Bulb

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-headlight-bulb.html

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How to Replace a Headlight Switch

http://schematicsdiagram.blogspot.com/2011/07/how-to-replace-headlight-switch.html

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How to Replace a Headlight Assembly

http://schematicsdiagram.blogspot.com/2011/08/how-to-replace-headlight-assembly.html

How to Replace a Park Light Assembly

http://schematicsdiagram.blogspot.com/2011/08/how-to-replace-park-light-assembly.html

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Low beam headlights Modification?

http://schematicsdiagram.blogspot.in/2012/04/low-beam-headlights-modification.html

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Headlight Assembly Removal On Honda Accord

http://technoanswers.blogspot.in/2012/06/headlight-assembly-removal-on-honda.html

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Honda Headlight Assembly Removal
http://schematicsdiagram.blogspot.in/2012/06/honda-headlight-assembly-removal.html

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How to Replace a Headlight Door

http://schematicsdiagram.blogspot.com/2011/08/how-to-replace-headlight-door.html

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How to replace HID headlight bulbs for lexus 400h?

http://schematicsdiagram.blogspot.com/2012/01/how-to-replace-hid-headlight-bulbs-for.html

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These will help.

Thanks.

It can be faulty low beam lamp or its connection issue for low beam lamps.

There are few solved helps links with proper solution to troubleshoot these issues.I suggest you to refer the links below.Click the link:----
Passenger side low beam out?

http://repairhelpcenter.blogspot.com/2012/01/passenger-side-low-beam-out.html

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Low beam HID light goes out? http://schematicsdiagram.blogspot.com/2012/01/low-beam-hid-light-goes-out.html
----------2007 Dodge Caliber: Low Beam Headlight Not working http://technoanswers.blogspot.in/2012/06/2007-dodge-caliber-low-beam-headlight.html
-------------Chevy Tahoe: Low Beam Lamps are not working? http://technoanswers.blogspot.in/2012/04/chevy-tahoe-low-beam-lamps-are-not.html
----------2001 Chevrolet Tahoe: Both Low Beam Lamps Not Working? http://technoanswers.blogspot.in/2012/04/2001-chevrolet-tahoe-both-low-beam.html
--------------2002 Toyota Tacoma: Low Beams not working? http://technoanswers.blogspot.in/2012/04/2002-toyota-tacoma-low-beams-not.html
-----------Low beam headlights Modification? http://schematicsdiagram.blogspot.in/2012/04/low-beam-headlights-modification.html
-----------DRL and Low beams not working? http://schematicsdiagram.blogspot.in/2012/04/drl-and-low-beams-not-working.html
-----------These will help.Thanks.

These trucks are known for bad multifuction switches.
the switch that i talk of is the signal switch , the handle is the switch, it bolts to side of steering column . this switch controls the signals and the headlights and high /low beams. the other thing is the headlight switch connector, the connector some times goes bad and starts to melt or just comes out of the connector. you will need to remove the cover to steering column, the screws are located under the bottom cover in holes. remove cover and check connector and then test for power if you have power going into switch but not coming out then switch is bad.

the last thing is to make sure the bulbs are good , make sure the headlight bulbs are good , and also the driving light bulbs, test for power at the connectors to those lights to.
You will need to do a little testing to find the problem.

It can be issue with headlight switch,but as its already been replaced.Try disconnecting high beam headlight wiring from headlight assembly and reconnect direct external wire from headlight switch to headlight assembly,then by switch see if headlight is getting off and turning on or not.
See below related help links,similar to your issue.Click the link below:----
Only high beams work but head lights not working on Ford F350?

http://howtobyme.blogspot.com/2011/11/only-high-beams-work-but-head-lights.html

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Only high beams working on GMC Savana?---------- High beams stopped working but headlights still work? http://howtobyme.blogspot.com/2011/11/highbeams-stopped-working-but.html
---------- • Working of Headlight switch? ----------

• Both headlight bulbs blow together? ----------

• Car headlight bulbs don't last long?
------------ Only one head light works on 2001 Dodge Caravan? http://howtobyme.blogspot.com/2011/11/only-one-head-light-works-on-2001-dodge.html

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these will help.
Thanks.

Does the green daytime indicator flash when you shift into gear?
If so, one or both high beam bulbs are burned out.

The wiring schematic changes drasticly depending on whether your vehicle is equipped with daytime running lamps or not. However, both systems have one thing in common...the low beams and the high beams get their grounds from the same place. If the high beams are working correctly, the ground is not your problem. The most common causes of low beams not working and high beams working are the multifunction switch (or as Toyota calls it: "Combination Switch") and if your vehicle has daytime running lamps, the Daytime Running Lamp Module could be the problem.

The blinking light is telling you that you have a headlight out, if you look the service light should be coming on when the light stops blinking.
Replace the head light and all should be fine.

not a 100% but sounds like switch is pooched...

perhaps i missed something here... lowbeams and daytime lights are about the same.... be that as it may... the merely obvious thing is that the low beams are burnt out.... next thing would be that the relay for the day time lights could be defective... it's often mounted on the firewall.

Robert