2004 Aviator Low beam light out

NO YOU HAVE TO REPLACE HIGH BEAM LIGHT BULBS WITH HIGH BEAM LIGHT BULBS BECAUSE HIGH BEAM LIGHT BULBS AND LOW BEAM LIGHT BULBS TWO DIFFERENT TYPES OF BULBS.WEAR CLEAN LATEX GLOVES HANDLING THE HEADLIGHT BULBS WHICH IS HALOGEN LIGHT BULBS, OIL FROM FINGERS OR HAND WILL CAUSE HALOGEN BULBS TO OVER HEAT BLOW OUT.

no you don't have to take it to a dealer...and you don't have to change both lights unless you want too...

Hi Every single time I have had a failure of low beam in a headlight without failure of high beam, it has been because the lamp bulb or halogen lamp module has reached the end of its serviceable life, not because of any wiring problems. Low beam burns out first because it is on the most. If low beam is lost simultaneously in both headlights, I would check fuse first, then the headlight switch. If low beam is lost on one side only, it is almost always going to be due to the bulb or lamp module needing to be replaced. In that case, replace them in both headlights because the other one will be going kaput in short order, as well.Also if you already replaced the fuse and bulb check the headlight dimmer control switch.
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If you have the HID bulbs check with an Autoparts store like Autozone. I believe the right and left headlights have separate Relays in the Powerbox. It is possible that there are 2 low beam and 2 high beam relays total. They pull too much power for both sides to be wired together and may wire the high beams separate too!

Removal & Installation To Remove:
WARNING
The halogen fog light bulb contains gas under pressure. The bulb may shatter if the glass envelope is scratched or if the bulb is dropped. Handle the bulb only by its base. Avoid touching the glass envelope.
NOTE: The headlight bulb should not be removed from the headlight assembly until just before a replacement bulb is installed. Removing the bulb for an extended period of time may affect headlight bulb performance. Contaminants may enter the headlight assembly where they can settle on the lens and reflector. Never turn on the headlights with the bulb removed.

1. Before servicing the vehicle, refer to the precautions in the beginning of this section. NOTE: Make sure that the headlight switch and the ignition switch are in the OFF position.
   
2. Remove the pin-type retainers, screws and the air deflector from the radiator.
3. Remove the three bolts and the headlight assembly.
4. Disconnect the electrical connector.
5. Remove the cover from the rear of the headlight assembly.
6. If equipped with HID, release the spring tabs to remove the low beam bulb, otherwise disconnect the electrical connector and remove the bulb.
7. Disconnect the electrical connector and remove the high beam bulb.

HID low beam headlight bulb

Standard low beam headlight bulb

High beam headlight bulb

To Install:

1. Place the headlight assembly in the proper position.
2. Install the cover from the rear of the headlight assembly.
3. Connect the electrical connector.
4. Install the three bolts and the headlight assembly.
5. Install the radiator air deflector.

replaced the low beam headlight on 2004 Navigator, but still wont work. fuses are good.

SYLVANIA H7 SILVERSTAR HIGH PERFORMANCE HALOGEN HEADLIGHT BULB -- 55 Watts, Single C-8 filament for use as either high beam or low beam; 100 percent legal halogen headlight bulbs; Features the whitest and brightest light colour similar to daylight for safer night driving; Meets all US FMVSS 108 and Canadian CMVSS 108 requirements. Fits Driver or Passenger Side Driver or Passenger Side Fits the following vehicle/s
2004 Audi S4 Base 8 Cyl 4.2L 2004: Base; 8 Cyl 4.2L RAMPAGE FOG LIGHT, BLACK METAL HOUSING, With round clear lens; Includes 100-Watt H3 halogen bulb, one lamp and a single bolt mounting system; Provides better illumination Fog Light

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  Fits the following vehicle/s: 2004 Audi S4 Base 8 Cyl 4.2L 2004: Base; 8 Cyl 4.2L;

Open hood and remove the radiator site shield and the air delector on top of the headlamp assembly. You will then see 2 clips that you will pull up and then remove the headlamp assembly.

I just Replaced a Low Beam Light bulb on a 2005 Buick La Sabre.

If You use a Metric socket and Remove the Two Silver bolts Attaching the headlight Assemble onto the metal surrounding the the lamp assembly it comes out to the front. This makes it much easier to access the bulb. Twist it counerclockwise & it comes out by pulling gently on the bulb. Then by realeasing a tab that is the socket holder bulb can be removed & replaced with a New #9006 low beam halogen light bulb. Wrap a Paper towel around the bulb & do NOT touch it with your bare hand as this wiil ruin a halogen bulb,

You may have the wrong part. Cross-reference the part number with the correct part number, which should be located in your owner's manual.

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