[Matt Ion]

wrote:
I finally got hold of a schematic (PDF file) for that car stereo which
I'm trying to use its CD-changer input for my MP3 player.

http://www.esnips.com/web/no-spam2-files

Anyone knowledgable in electronics who can figure out how this can be
done?
I just want to connect the headphone output from my MP3 player into the
car stereo without having to use a cassette adapter as I'm using now.

Looks like pins 1 and 3 are your CD in right and left, and pins 2 and 4 are
ground (use either or both).

Easiest way is probably to pick up a headphone extension cable and a male DIN
plug to fit the back of the deck; cut the female end off the extension, and
solder as appropriate into the DIN plug - red is typically right+, white or
black is left+, and the shield is ground.