Where is the Audio Aux jack in the 2005 Jetta? What do you need to connect? The salesman told me it had the MP3 player ready to use. Maybe that was my first mistake....

you said CAN , i bet you meant CAN'T or CAN NOT. right?
the AUX port is just a line input, analog audio input,
it dont know MP3 .
it only amplies the analog audio found there.
you connect any device, to AUX. push play on the device.
then put car radio in to AUX input mode and play. the audio.
that is all there is to it.
the external device does all the heavy lifting, reading a file, and decoding it (mp3 decode) and then sends raw analog audio out.

the cable is sold and radioshack, or walfart or many other stores,
Target, most MP3 players, come with this cable,
they use mini phone plugs, stereo, type,. (3 contacts)

you can replace your CD player with the same type, or you can buy the chinese product working well that I bought for my car priced 120 USD. that is a touch screened, with MP3, USD aux input ...etc.

This sounds like you do not have full usb functionality and it is diverting to the aux input. when aux is used you have to control the play and sound etc from the actual mp3 player and not the audio controls

to make life simple,you can buy an fm adaptor for your i player,so you can play your music in mums car......

If you plug some headphones into that jack and can hear your music from it then no you cant use it with an mp3 player.

The plug is actually at the rear of the set.remove the radio and connect an audio cable

yes you can connect any player with analog output

1 ensure your reciever is also set to AUX .
2 try another AUX device such as an MP3 player or CD player and check that your Receiver AUX function is working.
2. connect your Turntable to another input such as DVD, CD, or Tape to see if it works at that position.
ensure that the correct button is selected for which ever position you use.

MP3s are a different format from a regular CD. You can use an MP3 player through the AUX jack, but not a CD with MP3s on it.

I'am an M.B. tech- I do not beleive that this radio is mp3 compatable- iknow that the input you are refering to is used for ipod use. It very well could be that the head unit has to be programed(basically informed0 for an mp3- i would call the service dept. and ask to talk to ther best audio tech savay mechanic. Most likley the service writer wouldn.t know or give you false information because they do not stay on top of all the little tecnical changes. This fiber optic system has many programing features- most have to be done with as sds laptop(dealer software only) good luck