Generic MP3 player to Sony car stereo

How can I connect a generic MP3 player to a 10-year-old Sony CDX-C4840R car stereo? The stereo has a Line In, but this only works when the CD changer unit is connected to the special bus. I don't want to spend money on the special unit that Sony sells.

Phil B8 years ago
There have been a number of Instructables on this topic. Most of them provide less than totally satisfactory results (distortion, buzzing, etc.). I used an FM transmitter for a while, but it picks up a lot of interferrence between the player's audio output jack and the FM transmitter. If you are driving any distance other stations will bleed in on your chosen frequency. The most satisfactory arrangement I have used is a car kit for the cassette player, if you have a cassette player on your car stereo.
I don't know where to actually hack in, but you should be able to find the powe ramplifier input to connect a line in jack too. Alternatively, buy a line-to-FM adapter !