They told me that the fog light has bulb no 881 that is right or its h3

The covers pops off.

If it is a double filament bulb, try to rotate by 180 degrees in base, since there is a difference in power and touch of the bottom pins

it's easy just done it last night. unplug the wiring harness that goes to the fog light and then there is a bolt on the bottom of the fog light take it out and push the fog light forward and the hole assembly comes out just take off the back and change the bulb. my truck is a 2001 nissan frontier sc 4x4 and it took the h3 bulbs, got mine at wal-mart about $4.00

Read more: http://wiki.answers.com/Q/How_do_you_replace_the_light_bulb_in_a_2001_frontier_fog_light#ixzz1Lt4sxMGk

If this is the light thats on with the parking lights or the headlights on or the day time running light? a 3757 NAK is an Amber daytime rnning light and a clear daytime running light is a 3157K, both are right depending on your car. ( the cars made both ways depending on if it's a base model or not and did it come with optional headlights ( three options)). Then their are the headlights themselves as their are 6 possibilities. Easiest way is to remove the buld and read the number off or it or lay it on the counter of the auto prts store and let them match it up. A 3157 is a big bulb a dim marker light is a 194 and a bright marker light is a 921. Theres a fog driving light thats an H3, Small and very bright. Base model with HID low beams ( bright blue/white ) cost me $135 each and have a ballast attached ( my strore has them in stock) and up model has H1115 low beams. The bulb your asking about is likly to be the fog driving light and it's a H3

The bulb size is H3. If you search for your year, make model and H3 bulb you should find many options from 11 to 60 dollars.

They can be replaced by yourself, the removal instructions should be located in your Owner's Manual. You can buy the bulb at AutoZone, it is a Sylvania 881 and is $7.99

H3
Your auto part store should get it in stock.
warning Do not touch the bulb glass with your fingers or other oily surfaces. Reduced bulb life will result.
Hope it will help
Dan

2005 Forester - It is easiest to remove the fog assembly.

1. From underneath the vehicle pry out one plastic fastener to be able to bend the light weight plastic mud protector downward. You will see the underside of the fog light assembly with one 10mm bolt directly above you. Remove this bolt.
2. From the front of the vehicle unscrew one 10mm bolt at top of fog light (this is the shorter of the 2 by the way) and pry out one plastic rivet adjacent to it.
3. Carefully remove the fog assembly and disconnect 2-pin power connector by pulling up on the release. Carefully wiggle the housing out (no force req'd).
4. Unscrew the back from the housing and replace H3 bulbs. Take care not to touch the bulb while replacing.
5. Reverse to install.

Should take an hour at most.

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;

I wanted to know how to change the h3 bulbs in my fog lights in my 2003 subaru legacy.