How to Hardwire an MP3 to a Car

MP3 players are the standard in personal audio technology, but they can be a nuisance when driving, either because of static from FM transmitters or just getting in the driver's way. Hard-wiring an MP3 player to your vehicle's stereo can make for better audio fidelity and safer driving. Most auto stereos can be hard-wired without much difficulty.

Things You'll Need

  • RCA-to-1/8-inch cable
  • MP3 player converter
  • Drill
  • Drill bit
  • Driver bit

Hard-Wiring Using Free Auxillary Input

  • Determine if your vehicle's stereo has an auxiliary (AUX) input that accepts RCA cable connectors. Manufacturer's instruction manuals and websites as well as other online resources can provide this information. If it does have a free AUX input, an RCA-to-1/8-inch cable can be directly hard-wired into the stereo.

  • Remove the front panel, or bezel, that surrounds the stereo and heating/air conditioning controls. Some bezels can be pulled directly off, but most have screws that must be removed before removing the bezel. Manufacturer's instruction manuals usually indicate how to remove each vehicle model's bezel, as well as several online resources that have this information.

  • Remove the stereo from its bracket. This is usually done by loosening screws on either side of the stereo's faceplate and sliding it forward. Some stereos require special mini-tools for removal that are included with the vehicle or can be purchased from the manufacturer.

  • Locate the AUX inputs on the back of the stereo. They will be small RCA inputs, colored white and red.

  • Plug the RCA-to-1/8-inch cable's RCA plugs into the corresponding inputs on the back of the stereo.

  • Reinsert the stereo and screw it into place.

  • Pass the 1/8-inch end of the RCA-to-1/8-inch cable through the front of the bezel. You can do this either by drilling a small hole in the bezel or by passing it through the side of the bezel when the bezel is reattached.

  • Reattach the bezel. Your stereo is now hard-wired to use an MP3 player by switching to the AUX input on the stereo and connecting the 1/8-inch plug into the "LINE OUT" or headphone jack of any MP3 player.

Hard-Wiring Using a Converter

  • Purchase a converter if your stereo doesn't have a free auxiliary input. A converter allows a signal from an MP3 player to be played through a vehicle's stereo when free auxiliary inputs are not available. Different vehicles require different types of converters, and the correct type for your vehicle may be purchased from vehicle manufacturers or car audio retailers.

  • Remove the front panel, or bezel, that surrounds the stereo and heating/air conditioning controls. Some bezels can be pulled directly off but most have screws that must be removed before removing the bezel. Manufacturer's instruction manuals usually indicate how to remove each model's bezel, as well as several online resources that have this information.

  • Locate the input for the converter on the back of the stereo. These inputs most often have multi-pin connections and will match the plug on the converter.

  • Pass the input cable of the converter through the front of the bezel. You can do this by drilling a small hole in the bezel or by passing it through the side of the bezel when the bezel is reattached.

  • Reattach the bezel. Your stereo is now hard-wired to use an MP3 player by switching to the converter input and plugging the cable directly into your MP3 player.