More by the author:. Sure you can get radio FM modulator, but they don't work so great and are notorious for poor sound quality. This is probably the biggest challenge in the whole project.

Click you do any work on cars, then your shop manual will help, but also there's tons of user forums dedicated to specific car models. Most are stock friendly and will give you tips, just don't expect them to come do it for free or anything. Locate the CD changer plug and gain access to the pins for audio transmission from CD changer to head unit.

It should be something like the socket below in the lower right hand corner. They usually source about 8 or so pins arranged in a circle. Now here's where you have to do a bit of googling. Figure out what the pin layout is for your radio's CD changer.

Try searching with something like "Honda Accord CD changer pinout" I was able to find this layout for an Acura which was close to my Honda for the basis of mine. Remember, there's only a couple car makers, so stock a lot of similar equipment out there across brands. Honda Civic may be close to the Accord, and also close to an Acura. The same should apply for domestic cars made by the same manufacturer.

Once you have identified the audio pins, find a place to mount the internal radio. Be sure to keep the signals correctly matched to the right pins so you don't end up crossing channels or ground. Carefully drill a hole in the dash just larger than the jack to mount the external jack.

Add an Auxiliary (MP3/Ipod) Input to Your Car's Stock Radio

Use the old headphone cable and cut to the appropriate length to connect the internal and external jacks. Plug the cable into the internal jack, and solder the wire ends to the external jack. Take caution to match the pins refer to plug layout diagram if needed This cable serves as the quick-disconnect patch cable, should you need to remove your stereo or take apart your dash in the future.

Soldering directly without this patch cable could be a pain later if you ever need to remove the dash or stereo for repairs, etc. When drilling in the dash, be very careful and know exactly what's behind your drill bit so you don't accidentally drill into something important! This made an excellent location to mount the external jack since it was inconspicuous and also I "for" wire it up at my workbench instead of in the car. Choose the location you like best to mount the jack.

Introduction: Add an Auxiliary (MP3/Ipod) Input to Your Car's Stock Radio

Push the jack through your hole you drilled and use the nut supplied with the jack to screw onto the jack and hold it in place. I'd suggest a test run before you completely reinstall the stereo to find it doesn't work. Hook up the cables and give it a try. If everything sounds good, install the radio and put the dash back together. Once it's all together, all you have to do is put the CD changer on your "silent" CD, put it on track repeat and use the MP3 player to pump the tunes. You can see here's my setup for the jack installed.

Step 1: Remove Your Stock Radio From the Car

Now, in order to play the audio aux your MP3 player, we need to trick the CD changer into thinking it's playing a CD. The stereo doesn't know that the audio is really being supplied by your MP3 player instead of the CD changer.

In order to do this we just burn a special just click for source CD. It's got regular tracks, but there's no sound played. I click here the same file and added it multiple times to the CD hookup that Click had many tracks.

Just fill up the CD with these blank 5 minute tracks so even if you don't have the CD on repeat, you'll still hear nothing from the CD and everything from the MP3 player. Once you've burned the CD, aux it in your changer, put it on repeat play, and you're all set.

Turn on your MP3 player and test it out.