Hack an Aux Port into Your Old Car Stereo for Less Than $3

By October 10, 2014Automotive
How to Install an Auxiliary Port into Your Car Stereo

Want a bigger library of tunes on-demand? Most new stereos come with an auxiliary port built in for your phone or mp3 player, but if you bought your car during that nebulous time between CDs and mp3 players you’re probably stuck with the radio or CD player – and both those options pretty much suck.

For Redditor, Esplodies, it seemed that his only options were to pay the $95 fee for a dealership install or buy a new stereo entirely until he took matters into his own hands and hacked an audio-in port into his existing head unit for less than $3.

What You’ll Need

  • 5k resistor
  • CD-ROM audio cable
  • Speaker wire (2 feet)
  • 3.5mm audio jack

This works on some older CD players with a CD changer output and the idea is to use the CD-ROM audio cable and a resistor to plug into the rear CD changer port of your CD player and then wire that connection up to an auxiliary port.

Splice resistor into CD-ROM cable.

Esplodies cut the ends off his CD-ROM cable and spliced in a resistor to connect the trigger pin on each cable end together. A resistor is necessary for the stereo to recognize the input and he found the value he needed online.

CD changer output to aux port.

Using speaker wire, he connected the remaining wires coming out of the CD-ROM ends to the pins on the audio jack. And after a successful sound check with his iPod, he drilled a small hole to install the jack on the stereo’s face plate.

With the stereo back in place, the aux port looks like it’s been part of the stock head unit all along. Here’s hoping the electrical tape holds!

Check out his Imgur album for step-by-step photos and explore the Reddit thread for more hacking options.

Photos: Esplodies

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