The purpose of this blog is to log my Audi A4 problems and share the solutions I have found to those problems. Though this exchange we can all avoid the dealer and expensive repairs to common inexpensive problems.

Wednesday, April 21, 2010

How to Replace a Brake Light Bulb on an Audi A4 Avant Quattro 2002

Somehow I was not surprised to read in the owner's manual that I needed to take my car in to the dealer simply to change a bulb. The owner's manual blames this on the fact that cars are becoming increasingly complex (which is of course their own fault).
I called my local Audi dealer and they quoted $80 (USD) to perform the repair service. Instead I went to the auto parts store and bought a replacement bulb set which contained two (P21/5W) bulbs for $3.97 (USD).



First I carefully opened the circular cover with a small flat head screw driver (it just pops out).

Then, using a Phillips head screw driver, I carefully loosened the screw that holds the entire light assembly in place.  I knew I had the correct screw because as it got looser I was able to move the assembly slightly.  While the screw might have been able to be recovered with a magnet if it had fallen in the body, I was careful to avoid this by only loosening it a bit at time.

Once the assembly was free of the screw, I gently pulled back the rubber material so that it was free of that rubber block.

Next I began to carefully pull the assembly away from the center of the car.  In this case (because it's the left assembly) I began by pulling it gently to the left (not directly out because of the two plugs). I did this carefully as not to damage the plugs.

Once both plugs (top and bottom) were free of the body, the assembly was only connected by the wire.


Next I disconnected the socket from the assembly by carefully inserting a small flat head screw driver.

Finally I carefully separated the white piece from the assembly.  The stop light bulb was the one at the bottom (it had two filaments).  To remove it, I pressed down very gently and rotated it out counter-clockwise.


If you can' stand the thought of paying $100 just to have someone hook up a little cable underneath your dash to clear out a light, this is for you. We've all had that conversation... "Oh wow, you fixed it already? You just needed to erase the code, huh? Wait, how much? You're kidding. I saw what you did, I was standing right here the whole time, it took 10 minutes." THAT COSTS $100?!?!?!


  1. Thank you so much for this! I can't believe how much the dealership wanted to charge to replace the tail light cluster.

    I took your advice on loosening the screw very carefully, and as an insurance policy I made a "bridge" out of folded-up cardstock. It made everything much more comfortable for me, as I wasn't as nervous about dropping the screw in between the panels. For those who haven't done this, it's actually a very long screw (maybe 1.25"), so don't be too worried about dropping it, but take precautions.

    I also had some trouble getting it all put back together. It seemed like a tight fit, but the screw wasn't lining up and kept pushing the tail light out. I found that by gently hitting all around the edges of the tail light, and pushing in from the back side of the car while screwing the bolt, I was able to get it all together.

    One more tip for those doing this. Make sure you test the brakes and tail light to verify it's all hooked up correctly before putting it all back together. I was able to have it hanging by the electrical cable and facing forward so that I could see everything from the driver's position.

    1. Excellent explanation and pictures. My A4 Cabriolet (convertible) has slight differences - a bigger twist off access plug at the REAR of the plastic light fixture on the trunk liner. It does not have that white assembly on the back of the plastic light fixture - the bulb holders are directly exposed. Be careful to line dual filiment bulbs so that BOTH contacts are made - you can actually put the bulb in 90 degrees off and make only one contact. Those two red plugs on the plastic light fixture actually slide over metal grommets on the car. They need to be lined up and slid back on from the outside toward the center (reverse of how slid them off - they will not snap off/on, but slide)

  2. I have the same year and model and have a lighting issue I can't find any info about.

    The passenger side top rear light is out since I bought the car used. The drivers side top rear light comes on only when the fog lights are on.

    Took it to the dealer and they said it was designed that way. Called Audi corporate and they said the same thing. Dealer said there are no wires for the light in the rear on the right.

    Does your car have lights on the top on both rear sides? Could this be a flaw on their part?

  3. The Upper left light is an Autobaun light. Euro requirement thats not required in U.S. but, they install the upper left light anyways.

  4. This is great thank you! I'm a complete novice to stuff like this my brake light bulb has just gone so this will probably save me finding a garage. Assuming it would be something similar for reverse lights too?

  5. This comment has been removed by a blog administrator.

  6. Thank you for sharing this! I was so worried I wouldn't find out a how to on how to fix my brake light. I thought that I might have to go to an Audi dealer just to get that fixed! That would have been embarrassing- thanks again for helping out the uneducated on simple car fixes like this.

  7. Thank-you so much! I just succeeded in replacing my brake light and it only took about 10 minutes! Nice to save some money!

  8. This comment has been removed by a blog administrator.

  9. I'm loving reading about your own perspective in this post. I actually recognize how well formatted it is and just how clear your material has been composed. You've carried out an extremely nice job of making yourself heard.
    Audi Greensboro