XM is connected to the extension port at the back of the stereo. To be able to add AUX you still need to get the AUX adapter. It usually has vehicle cable that goes to that extension port, aux box and aux cord. Here is the link to the GROM AUX product, it explains how it works: http://gromaudio.com/store/aux_adapt...-aux-hon1.html
It actually retains your XM.

 

Metraonline.com and USAspec.com also have interfaces that let you use your XM button as an aux input button - similar to the Grom interface.

 

I disconnected my XM line in my trunk because I didn't want to cycle through it all the time. Can I just plug a AUX adapter to that line and run the AUX cable under the car or carpet to the front so I can plug a iPhone or something into it?

This would be nice provided i don't have to take apart my console.

 

you can't tap into the XM line at the trunk - it is set up for a separate type of signal, like the antenna or controller.

to get an aux input you need to buy an adapter: visit pac-audio dot com and enter your vehicle information. you can get an aux input or an iphone input (charging and control of iphone). the interface units are over $100 and require you remove the dash, remove the radio, and interface these units. however, they come with mating plugs so you (usually) aren't cutting wires. removing the factory radio is fairly easy, tell me your make/model/trim and i can give you a link to instructions.

if you aren't comfortable removing your dash trim, you can pay a local shop to do it.

 

Yes that is correct - you will still need to connect behind the stereo. It is not difficult to remove the stereo, there are some videos and manuals available.

 

ccoltmanm, if you are in northern CA - I can refer you to some shops that can do the install at a decent price.

 

if you visit metraonline dot com you can search for a dash kit for your vehicle and download the PDF for instructions for free, which will show you how to remove your factory radio.

 

No, I live in Chicago. The dash is nice, and my car's interior is in good shape, I dont' think i want to take it apart. I will stick with CD's for now.

 

Thanks for the link though, to Mertaonline, really nice pdf's.